ferric-chloride-induced-canine-carotid-artery-thrombosis-large-animal

Ferric Chloride-induced Canine Carotid Artery Thrombosis: A Large Animal Model of Vascular Injury

Occlusive arterial thrombosis leading to cerebral ischemic stroke and myocardial infarction contributes to ~13 million deaths every year globally. Here, ...

quantification-cerebral-perfusion-using-laser-speckle-imaging-infarct

Quantification of Cerebral Perfusion using Laser Speckle Imaging and Infarct Volume using MRI in a Pre-clinical Model of Posterior Circulation Stroke

Background: Basilar artery occlusion (BAO) is a subset of posterior circulation stroke that carries a mortality as high as 90%.&#160; The current clinical ...

Ohio State University

The Ohio State University Medical Center

Lipid peroxidation (LPO) is considered a major factor in damage spread after spinal cord injury (SCI). Therapies that limit LPO after SCI have demonstrated some utility in clinical trials, but more effective treatments are needed. In the present study the effects of augmenting SC levels of the endogenous antioxidant glutathione (GSH) on LPO after SCI were studied in a rat contusion injury model. A significant decrease in GSH occurred 1h after SCI which was paralleled by increases of 123% in malondialdehyde (MDA) and >500% in the 4-hydroxyalkenals (4-HA's), two LPO products. SC irrigation with gamma-glutamylcysteine (GC) preserved GSH and reduced 4-HA's below naive levels but had no effect on MDA. By 24 h after SCI, MDA returned to naive levels but 4-HA's were still elevated. Once again, GC treatment reduced 4-HA's. 4-HA's are much more reactive than MDA and are considered among the most toxic LPO products. These results suggest that (1) conditions after SCI may favor particular branches of the LPO pathway leading to differential LPO product levels, (2) MDA measurement is not by itself an adequate test for the presence or magnitude of LPO after SCI, (3) binding of GSH to 4-HA's may be an important mechanism by which the GSH system confers protection against LPO after SCI, and (4) SC GSH can be augmented after trauma by local irrigation with GC. These results also suggest that GSH augmentation may be an effective strategy for curtailment of LPO-mediated damage in acute phase SCI.

Effect of glutathione augmentation on lipid peroxidation after spinal cord injury.

Producci&oacute;n de peroxinitrito aumenta durante la patogenesia de numerosos trastornos card&iacute;acos (por ejemplo, insuficiencia card&iacute;aca). Sin embargo, pocos estudios han investigado el mecanismo a trav&eacute;s del cual peroxinitrito ejerce efectos adren&eacute;rgico. As&iacute;, el prop&oacute;sito de este estudio es investigar la contribuci&oacute;n de fosfolamdano (PLB), una prote&iacute;na de acoplamiento excitaci&oacute;n-contracci&oacute;n cr&iacute;tica, a la disfunci&oacute;n inducida por peroxinitrito.

Selecci&oacute;n de fosfolamdano por peroxinitrito disminuye est&iacute;mulo beta-adren&eacute;rgico en cardiomiocitos.

&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x4EA7;&#x91CF;&#x589E;&#x52A0;&#x671F;&#x95F4;&#x8BB8;&#x591A;&#x5FC3;&#x810F;&#x75BE;&#x60A3; (&#x5982;&#x5FC3;&#x8870;) &#x7684;&#x53D1;&#x75C5;&#x673A;&#x5236;&#x3002;&#x4F46;&#x662F;&#xFF0C;&#x6709;&#x9650;&#x7684;&#x7814;&#x7A76;&#x8C03;&#x67E5;&#x4E86;&#x8BE5;&#x673A;&#x5236;&#x7684;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x901A;&#x8FC7;&#x65BD;&#x52A0; anti-adrenergic &#x7684;&#x5F71;&#x54CD;&#x3002;&#x56E0;&#x6B64;&#xFF0C;&#x8FD9;&#x9879;&#x7814;&#x7A76;&#x7684;&#x76EE;&#x7684;&#x662F;&#x8C03;&#x67E5;&#x7684;&#x5173;&#x952E;&#x5174;&#x594B;&#x6536;&#x7F29;&#x5076;&#x8054;&#x86CB;&#x767D;&#xFF0C;&#x5BF9;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x5F15;&#x8D77;&#x7684;&#x529F;&#x80FD;&#x969C;&#x788D; &#xFF08;&#x516C;&#x5171;&#x5C0F;&#x5DF4;&#xFF09;&#xFF0C;&#x78F7;&#x8D21;&#x732E;&#x3002;

&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x6240;&#x9488;&#x5BF9;&#x7684;&#x78F7;&#x51CF;&#x5C11; beta-adrenergic &#x523A;&#x6FC0;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#x3002;

Peroxynitrite production increases during the pathogenesis of numerous cardiac disorders (e.g. heart failure). However, limited studies have investigated the mechanism through which peroxynitrite exerts anti-adrenergic effects. Thus, the purpose of this study is to investigate the contribution of phospholamban (PLB), a critical excitation-contraction coupling protein, to the peroxynitrite-induced dysfunction.

Targeting of phospholamban by peroxynitrite decreases beta-adrenergic stimulation in cardiomyocytes.

Peroxynitrite production augmente au cours de la pathogen&egrave;se de nombreux troubles cardiaques (par exemple l&#39;insuffisance cardiaque). Cependant, peu d&#39;&eacute;tudes ont &eacute;tudi&eacute; le m&eacute;canisme par lequel peroxynitrite exerce des effets antiadr&eacute;nergiques. Ainsi, le but de cette &eacute;tude est d&#39;&eacute;tudier la contribution de phospholamban (PLB), une prot&eacute;ine de couplage excitation-contraction critique, &agrave; la dysfonction induite par le peroxynitrite.

Ciblage de phospholamban par le peroxynitrite diminue la stimulation b&ecirc;ta-adr&eacute;nergique dans les cardiomyocytes.

Peroxynitrite Produktion erh&ouml;ht sich w&auml;hrend der Entstehung von zahlreichen kardialen Erkrankungen (z.B. Herzinsuffizienz). Jedoch haben begrenzte Studien untersucht den Mechanismus durch die Peroxynitrite anti-adrenergic Effekte aus&uuml;bt. Somit ist der Zweck dieser Studie zu den Beitrag von Phospholamban (PLB), eine kritische Anregung-Kontraktion Kupplung Protein, um die Peroxynitrite-induzierte Dysfunktion zu untersuchen.

Ausrichtung von Phospholamban von Peroxynitrite verringert beta-adrenergic Anregung in den Cardiomyocytes.

Perossinitrito produzione aumenta durante la patogenesi di numerosi disturbi cardiaci (ad esempio insufficienza cardiaca). Tuttavia, limitati studi hanno indagato il meccanismo attraverso il quale il perossinitrito esercita effetti anti-adrenergic. Cos&igrave;, lo scopo di questo studio &egrave; di indagare il contributo di phospholamban (PLB), una proteina di accoppiamento eccitazione-contrazione critici, per la disfunzione indotta da perossinitrito.

Targeting della phospholamban di perossinitrito diminuisce la stimolazione beta-adrenergici nei cardiomyocytes.

&#x30DA;&#x30EB;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x751F;&#x7523;&#x6570;&#x591A;&#x304F;&#x5FC3;&#x81D3;&#x75BE;&#x60A3; &#xFF08;&#x4F8B;&#x3048;&#x3070;&#x5FC3;&#x4E0D;&#x5168;&#xFF09; &#x306E;&#x75C5;&#x614B;&#x4E2D;&#x306B;&#x5897;&#x52A0;&#x3057;&#x307E;&#x3059;&#x3002;&#x3057;&#x304B;&#x3057;&#x3001;&#x9650;&#x3089;&#x308C;&#x305F;&#x7814;&#x7A76;&#x306F;&#x3001;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x3092;&#x8ABF;&#x3079;&#x305F;&#x3069;&#x306E;&#x30D1;&#x30FC;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x3092;&#x901A;&#x3057;&#x3066;&#x4F4E;&#x52B9;&#x679C;&#x3092;&#x767A;&#x63EE;&#x3057;&#x307E;&#x3059;&#x3002;&#x3057;&#x305F;&#x304C;&#x3063;&#x3066;&#x3001;&#x3053;&#x306E;&#x7814;&#x7A76;&#x306E;&#x76EE;&#x7684;&#x306F;&#x3001;phospholamban (PLB) &#x30D1;&#x30FC;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x8A98;&#x8D77;&#x6A5F;&#x80FD;&#x4E0D;&#x5168;&#x306E;&#x91CD;&#x8981;&#x306A;&#x8208;&#x596E;&#x53CE;&#x7E2E;&#x7D50;&#x5408;&#x30BF;&#x30F3;&#x30D1;&#x30AF;&#x8CEA;&#x306E;&#x8CA2;&#x732E;&#x5EA6;&#x3092;&#x8ABF;&#x67FB;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x3067;&#x3059;&#x3002;

Phospholamban &#x306E;&#x30DA;&#x30EB;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x306B;&#x3088;&#x308B;&#x30BF;&#x30FC;&#x30B2;&#x30C3;&#x30C8;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x306B;&#x304A;&#x3051;&#x308B; &beta;-&#x30A2;&#x30C9;&#x30EC;&#x30CA;&#x30EA;&#x30F3;&#x523A;&#x6FC0;&#x304C;&#x6E1B;&#x5C11;&#x3057;&#x307E;&#x3059;&#x3002;

Peroxynitrite &#xC0DD;&#xC0B0; &#xC218;&#xB9CE;&#xC740; &#xC2EC;&#xC7A5; &#xC7A5;&#xC560; (&#xC608;: &#xC2EC;&#xC7A5; &#xB9C8;&#xBE44;)&#xC758; &#xBCD1; &#xC778; &#xC911; &#xC99D;&#xAC00;&#xD569;&#xB2C8;&#xB2E4;. &#xADF8;&#xB7EC;&#xB098;, &#xC81C;&#xD55C; &#xB41C; &#xC5F0;&#xAD6C; &#xC870;&#xC0AC;&#xB294; &#xBA54;&#xCEE4;&#xB2C8;&#xC998;&#xC740; peroxynitrite &#xD1B5;&#xD574; anti-adrenergic &#xD6A8;&#xACFC; &#xBC1C;&#xD718; &#xD55C;&#xB2E4;. &#xB530;&#xB77C;&#xC11C;,&#xC774; &#xC5F0;&#xAD6C;&#xC758; &#xBAA9;&#xC801;&#xC740; phospholamban (&#xCCA8; &#xB450; &#xBD80;&#xD558;) peroxynitrite &#xC720;&#xB3C4; &#xC7A5;&#xC560;&#xC5D0; &#xC911;&#xC694; &#xD55C; &#xC790;&#xADF9;-&#xC218;&#xCD95; &#xACB0;&#xD569; &#xB2E8;&#xBC31;&#xC9C8;&#xC758; &#xAE30;&#xC5EC;&#xB3C4; &#xC870;&#xC0AC;.

Peroxynitrite &#xD558; &#xC5EC; phospholamban&#xC758; &#xD0C0;&#xAC9F;&#xD305; cardiomyocytes beta-adrenergic &#xC790;&#xADF9; &#xAC10;&#xC18C;.

Signaling via endothelial nitric oxide synthase (NOS3) limits the heart's response to beta-adrenergic (beta-AR) stimulation, which may be protective against arrhythmias. However, mechanistic data are limited. Therefore, we performed simultaneous measurements of action potential (AP, using patch clamp), Ca2+ transients (fluo 4), and myocyte shortening (edge detection). L-type Ca2+ current (ICa) was directly measured by the whole cell ruptured patch-clamp technique. Myocytes were isolated from wild-type (WT) and NOS3 knockout (NOS3-/-) mice. NOS3-/- myocytes exhibited a larger incidence of beta-AR (isoproterenol, 1 microM)-induced early afterdepolarizations (EADs) and spontaneous activity (defined as aftercontractions). We also examined ICa, a major trigger for EADs. NOS3-/- myocytes had a significantly larger beta-AR-stimulated increase in ICa compared with WT myocytes. In addition, NOS3-/- myocytes had a larger response to beta-AR stimulation compared with WT myocytes in Ca2+ transient amplitude, shortening amplitude, and AP duration (APD). We observed similar effects with specific NOS3 inhibition [L-N5-(1-iminoethyl)-ornithine (l-NIO), 10 microM] in WT myocytes as with NOS3 knockout. Specifically, l-NIO further increased isoproterenol-stimulated EADs and aftercontractions. l-NIO also further increased the isoproterenol-stimulated ICa, Ca2+ transient amplitude, shortening amplitude, and APD (all P < 0.05 vs isoproterenol alone). l-NIO had no effect in NOS3-/- myocytes. These results indicate that NOS3 signaling inhibits the beta-AR response by reducing ICa and protects against arrhythmias. This mechanism may play an important role in heart failure, where arrhythmias are increased and NOS3 expression is decreased.

Endothelial nitric oxide synthase decreases beta-adrenergic responsiveness via inhibition of the L-type Ca2+ current.

Studies have shown that neuronal nitric oxide synthase (nNOS, NOS1) knockout mice (NOS1-/-) have increased or decreased contractility, but consistently have found a slowed rate of intracellular Ca2+ ([Ca2+]i) decline and relengthening. Contraction and [Ca2+]i decline are determined by many factors, one of which is phospholamban (PLB). The purpose of this study is to determine the involvement of PLB in the NOS1-mediated effects. Force-frequency experiments were performed in trabeculae isolated from NOS1-/- and wild-type (WT) mice. We also simultaneously measured Ca2+ transients (Fluo-4) and cell shortening (edge detection) in myocytes isolated from WT, NOS1-/-, and PLB-/- mice. NOS1-/- trabeculae had a blunted force-frequency response and prolonged relaxation. We observed similar effects in myocytes with NOS1 knockout or specific NOS1 inhibition with S-methyl-l-thiocitrulline (SMLT) in WT myocytes (i.e., decreased Ca2+ transient and cell shortening amplitudes and prolonged decline of [Ca2+]i). Alternatively, NOS1 inhibition with SMLT in PLB-/- myocytes had no effect. Acute inhibition of NOS1 with SMLT in WT myocytes also decreased basal PLB serine16 phosphorylation. Furthermore, there was a decreased SR Ca2+ load with NOS1 knockout or inhibition, which is consistent with the negative contractile effects. Perfusion with FeTPPS (peroxynitrite decomposition catalyst) mimicked the effects of NOS1 knockout or inhibition. beta-Adrenergic stimulation restored the slowed [Ca2+]i decline in NOS1-/- myocytes, but a blunted contraction remained, suggesting additional protein target(s). In summary, NOS1 inhibition or knockout leads to decreased contraction and slowed [Ca2+]i decline, and this effect is absent in PLB-/- myocytes. Thus NOS1 signaling modulates PLB serine16 phosphorylation, in part, via peroxynitrite.

Neuronal nitric oxide synthase signaling within cardiac myocytes targets phospholamban.

&#x8BB8;&#x591A;&#x7814;&#x7A76;&#x5DF2;&#x7ECF;&#x8BC1;&#x660E;&#x5728;&#x5FC3;&#x808C;&#xFF0C;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x7684;&#x53CC;&#x5411;&#x4F5C;&#x7528;&#xFF0C;&#x4F46;&#x51E0;&#x9879;&#x7814;&#x7A76;&#x8C03;&#x67E5;&#x4E86; beta-adrenergic &#x7684;&#x54CD;&#x5E94;&#x6B64;&#x53CC;&#x5411;&#x4F5C;&#x7528;&#x548C;&#x5176;&#x4F9D;&#x8D56;&#x4E8E;&#x6536;&#x7F29;&#x72B6;&#x6001;&#x3002;&#x6211;&#x4EEC;&#x4EE5;&#x524D;&#x5DF2;&#x7ECF;&#x8868;&#x660E;&#xFF0C;&#x9AD8; 3-morpholinosydnonimine &#xFF08;&#x5055;-1&#xFF09; &#xFF08;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x7684;&#x6765;&#x6E90;&#x3001; 200 &#x5FAE;&#x6469;&#x5C14;/&#x5347;&#xFF09; &#x671F;&#x95F4;&#x5728;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#x4E2D;&#x7684;&#x6700;&#x5927; beta-adrenergic &#x523A;&#x6FC0;&#x4EA7;&#x751F;&#x91CD;&#x5927;&#x7684; anti-adrenergic &#x5F71;&#x54CD;&#x3002;&#x5728;&#x5F53;&#x524D;&#x7684;&#x7814;&#x7A76;&#x4E2D;&#xFF0C;&#x6211;&#x4EEC;&#x63A8;&#x6D4B;&#x9AD8;&#x5055; 1 &#x7684;&#x8D1F;&#x9762;&#x5F71;&#x54CD;&#x5C06;&#x5728;&#x9AD8;&#x6536;&#x7F29;&#x7684;&#x56FD;&#x5BB6;&#xFF0C;&#x6700;&#x5927;&#xFF0C;&#x800C;&#x4F4E;&#x5055; 1 &#xFF08;10 &#x6469;&#x5C14;/&#x5347;) &#x4F1A;&#x7684;&#x79EF;&#x6781;&#x5F71;&#x54CD;&#x5728;&#x4F4E;&#x6536;&#x7F29;&#x671F;&#x95F4;&#x5360;&#x4E3B;&#x5BFC;&#x5730;&#x4F4D;&#x3002;&#x5C0F;&#x9F20;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#x662F;&#x5B57;&#x6BB5;&#x4EE5; 1 hz &#x7684;&#x9891;&#x7387;&#xFF0C;&#x523A;&#x6FC0;&#x548C; [Ca(2+)](i) &#x77AC;&#x53D8;&#x548C;&#x7F29;&#x77ED;&#x5F55;&#x3002;&#x540E;&#x88AB;&#x5F02;&#x4E19;&#x80BE;&#x4E0A;&#x817A;&#x7D20; (ISO) (beta-adrenergic &#x6FC0;&#x52A8;&#x5242;&#x3001; 0.01 &#x5FAE;&#x6469;&#x5C14;/&#x5347;&#xFF09; &#x523A;&#x6FC0;&#x3001; 200 &#x5FAE;&#x6469;&#x5C14;/&#x5347;&#x5055;-1 &#x5F15;&#x8D77;&#x4E24;&#x79CD;&#x622A;&#x7136;&#x4E0D;&#x540C;&#x7684;&#x73B0;&#x8C61;&#x3002;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#x7ECF;&#x5386; ISO &#x5927;&#x54CD;&#x5E94;&#x8868;&#x660E;&#x5927;&#x91CF;&#x51CF;&#x5C11;&#x6536;&#x7F29;&#xFF0C;&#x800C;&#x53C2;&#x5C55; ISO &#x8C26;&#x865A;&#x56DE;&#x5E94;&#x7684;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#x6536;&#x7F29;&#x7684;&#x8FDB;&#x4E00;&#x6B65;&#x4E0A;&#x5347;&#x3002;&#x6B64;&#x5916;&#xFF0C;10 &#x6469;&#x5C14;/&#x5347;&#x5055;-1 &#x59CB;&#x7EC8;&#x5728;&#x4F4E; ISO &#x523A;&#x6FC0;&#xFF0C;&#x589E;&#x52A0;&#x6536;&#x7F29;&#x529B;&#xFF0C;&#x4F46;&#x671F;&#x95F4;&#x6700;&#x5927;&#x7684; ISO (1 &#x6469;&#x5C14;/&#x5347;) &#x523A;&#x6FC0;&#x5E76;&#x65E0;&#x5F71;&#x54CD;&#x3002;&#x5055;-1 &#x5728; 10 &#x5FAE;&#x6469;&#x5C14;/&#x5347;&#x4E5F;&#x589E;&#x52A0;&#x57FA;&#x5E95;&#x6536;&#x7F29;&#x529B;&#x3002;&#x6709;&#x8DA3;&#x7684;&#x662F;&#xFF0C;&#x5055; 1 &#x751F;&#x4EA7;&#x78F7;&#x6316;&#x7A7A;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#xFF0C;&#x53EA;&#x6709;&#x4E00;&#x4E2A;&#x6761;&#x4EF6;&#x4E0B;&#x7684;&#x6536;&#x7F29;&#x4F5C;&#x7528;&#x63D0;&#x4F9B;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x7684;&#x53CC;&#x76F8;&#x6548;&#x5E94;&#x7684;&#x6F5C;&#x5728;&#x673A;&#x5236;&#x3002;&#x8FD9;&#x4E9B;&#x7ED3;&#x679C;&#x63D0;&#x4F9B;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x4E0E;&#x8C03;&#x5236; beta-adrenergic &#x54CD;&#x5E94;&#x80FD;&#x529B;&#x548C;&#x8C03;&#x8282;&#x57FA;&#x5E95;&#x51FD;&#x6570;&#x548C;&#x4F4E;&#x6C34;&#x5E73;&#x7684; beta-adrenergic &#x523A;&#x6FC0;&#x4F4E;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x7684;&#x9AD8;&#x6C34;&#x5E73;&#x9AD8;&#x8FC7;&#x6C27;&#x4E9A;&#x785D;&#x9178;&#x76D0;&#x7684;&#x53CC;&#x5411;&#x4F5C;&#x7528;&#x7684;&#x660E;&#x786E;&#x8BC1;&#x636E;&#x3002;

&#x53CC;&#x76F8;&#x5055;-1 &#x7684;&#x5F71;&#x54CD;&#x662F;&#x4F9D;&#x8D56;&#x4E8E;&#x5FC3;&#x808C;&#x7EC6;&#x80DE;&#x6536;&#x7F29;&#x72B6;&#x6001;&#x3002;

Many studies have demonstrated a biphasic effect of peroxynitrite in the myocardium, but few studies have investigated this biphasic effect on beta-adrenergic responsiveness and its dependence on contractile state. We have previously shown that high 3-morpholinosydnonimine (SIN-1) (source of peroxynitrite, 200 micromol/L) produced significant anti-adrenergic effects during maximal beta-adrenergic stimulation in cardiomyocytes. In the current study, we hypothesize that the negative effects of high SIN-1 will be greatest during high contractile states, whereas the positive effects of low SIN-1 (10 micromol/L) will predominate during low contractility. Isolated murine cardiomyocytes were field stimulated at 1 Hz, and [Ca(2+)](i) transients and shortening were recorded. After submaximal isoproterenol (ISO) (beta-adrenergic agonist, 0.01 micromol/L) stimulation, 200 micromol/L SIN-1 induced two distinct phenomena. Cardiomyocytes undergoing a large response to ISO showed a significant reduction in contractility, whereas cardiomyocytes exhibiting a modest response to ISO showed a further increase in contractility. Additionally, 10 micromol/L SIN-1 always increased contractility during low ISO stimulation, but had no effect during maximal ISO (1 micromol/L) stimulation. SIN-1 at 10 micromol/L also increased basal contractility. Interestingly, SIN-1 produced a contractile effect under only one condition in phospholamban-knockout cardiomyocytes, providing a potential mechanism for the biphasic effect of peroxynitrite. These results provide clear evidence for a biphasic effect of peroxynitrite, with high peroxynitrite modulating high levels of beta-adrenergic responsiveness and low peroxynitrite regulating basal function and low levels of beta-adrenergic stimulation.

Biphasic effect of SIN-1 is reliant upon cardiomyocyte contractile state.

De nombreuses &eacute;tudes ont d&eacute;montr&eacute; un effet biphasique de peroxynitrite dans le myocarde, mais peu d&#39;&eacute;tudes ont &eacute;tudi&eacute; cet effet biphasique sur la r&eacute;activit&eacute; de b&ecirc;ta-adr&eacute;nergique et sa d&eacute;pendance sur l&#39;&eacute;tat contractile. Nous avons d&eacute;j&agrave; montr&eacute; que haute 3-morpholinosydnonimine (SIN-1) (source du peroxynitrite, 200 micromol/L) produit des effets antiadr&eacute;nergiques significatives au cours de la stimulation b&ecirc;ta-adr&eacute;nergique maximale dans les cardiomyocytes. Dans la pr&eacute;sente &eacute;tude, nous &eacute;mettons l&#39;hypoth&egrave;se que les effets n&eacute;gatifs du haut SIN-1 sera la plus grandes au cours des &Eacute;tats contractiles &eacute;lev&eacute;s, alors que les effets positifs de la faible volont&eacute; (10 micromol/L) de SIN-1 pr&eacute;dominent durant la contractilit&eacute; faible. Cardiomyocytes murins isol&eacute;s &eacute;taient champ stimul&eacute;e &agrave; 1 Hz, et [le raccourcissement et Ca(2+)](i) transitoires ont &eacute;t&eacute; enregistr&eacute;s. Apr&egrave;s sous-maximale isoprot&eacute;r&eacute;nol (ISO) (agoniste b&ecirc;ta-adr&eacute;nergique, 0,01 micromol/L) stimulation, 200 micromol/L SIN-1 induit deux ph&eacute;nom&egrave;nes distincts. Cardiomyocytes subissant une grande r&eacute;ponse &agrave; l&#39;ISO montrent une r&eacute;duction significative de la contractilit&eacute;, alors que les cardiomyocytes pr&eacute;sentant une r&eacute;ponse modeste &agrave; l&#39;ISO a montr&eacute; une nouvelle augmentation de contractilit&eacute;. En outre, 10 micromol/L SIN-1 a augment&eacute; de contractilit&eacute; durant une stimulation faible ISO toujours, mais n&#39;a aucun effet lors de la stimulation maximale ISO (1 micromol/L). SIN-1 &agrave; 10 micromol/L a &eacute;galement augment&eacute; la contractilit&eacute; basale. Fait int&eacute;ressant, SIN-1 a produit un effet contractile sous seule condition dans les cardiomyocytes phospholamban-knockout, fournissant un m&eacute;canisme potentiel pour l&#39;effet biphasique du peroxynitrite. Ces r&eacute;sultats fournissent des preuves claires pour un effet biphasique de peroxynitrite, avec haute peroxynitrite modulant de hauts niveaux de r&eacute;activit&eacute; b&ecirc;ta-adr&eacute;nergique et faible peroxynitrite r&eacute;glementant la fonction basale et faibles niveaux de stimulation b&ecirc;ta-adr&eacute;nergique.

Effet biphasique de SIN-1 est d&eacute;pendante de l&#39;&eacute;tat contractile cardiomyocyte.

Viele Studien haben gezeigt, eine biphasische Wirkung von Peroxynitrite im Myokard, aber nur wenige Studien haben diese biphasische Wirkung auf beta-adrenergic Reaktionsf&auml;higkeit und seine Abh&auml;ngigkeit von kontraktilen Zustand untersucht. Wir haben bereits gezeigt, dass diese hoch 3-Morpholinosydnonimine (SIN-1) (Quelle der Peroxynitrite, 200 Mikromol/L) deutliche anti-adrenergic Effekte w&auml;hrend der maximale beta-adrenergic Stimulation in den Cardiomyocytes produziert. In der aktuellen Studie vermuten wir, dass die negativen Auswirkungen der hohen SIN-1 w&auml;hrend hoher KONTRAKTILER Zust&auml;nden, gr&ouml;&szlig;te sein werden, w&auml;hrend die positiven Effekte der niedrigen SIN-1 (10 Mikromol/L) wird w&auml;hrend der niedrigen Kontraktilit&auml;t &uuml;berwiegen. Isolierte murinen Cardiomyocytes waren Feld von 1 Hz stimuliert, und [Ca(2+)](i) Transienten und Verk&uuml;rzung wurden aufgezeichnet. Nach submaximal Isoproterenol (ISO) (beta-adrenergic-Agonist, 0,01 Mikromol/L) Stimulation, 200 Mikromol/L SIN-1 induzierte zwei unterschiedliche Ph&auml;nomene. Cardiomyocytes durchl&auml;uft eine gro&szlig;e Antwort auf ISO zeigte eine signifikante Reduktion in Kontraktilit&auml;t, w&auml;hrend Cardiomyocytes pr&auml;sentiert eine bescheidene Antwort auf ISO eine weitere Steigerung der Kontraktilit&auml;t zeigte. Zus&auml;tzlich 10 Mikromol/L SIN-1 immer erh&ouml;hte Kontraktilit&auml;t w&auml;hrend der niedrigen ISO-Stimulation, aber hatte keine Wirkung, w&auml;hrend der maximale ISO (1 Mikromol/L) Stimulation. SIN-1 bei 10 Mikromol/L erh&ouml;ht auch basale Kontraktilit&auml;t. Interessanterweise produzierte SIN-1 einen kontraktilen Effekt unter einer Bedingung in Phospholamban-ko Cardiomyocytes, Bereitstellen eines m&ouml;glichen Mechanismus f&uuml;r die biphasische Wirkung von Peroxynitrite. Diese Ergebnisse liefern klare Beweise f&uuml;r eine biphasische Wirkung von Peroxynitrite, mit hohen Peroxynitrite hohe beta-adrenergic Reaktionsf&auml;higkeit und niedrige Peroxynitrite Regulierung basale Funktion und niedrige Niveaus der beta-adrenergic Stimulation moduliert.

Biphasische wirkt SIN-1 auf Cardiomyocyte kontraktilen Zustand angewiesen.

Molti studi hanno dimostrato un effetto bifasico di perossinitrito nel miocardio, ma pochi studi hanno indagato questo effetto bifasico sulla reattivit&agrave; beta-adrenergici e sua dipendenza dello stato contrattile. Abbiamo precedentemente dimostrato che alte 3-morpholinosydnonimine (SIN-1) (fonte di perossinitrito, 200 micromol/L) prodotto significativi effetti anti-adrenergic durante la massima stimolazione beta-adrenergici nei cardiomyocytes. In questo studio, si ipotizza che gli effetti negativi dell&#39;alta SIN-1 sar&agrave; pi&ugrave; grandi durante gli Stati contrattili alti, considerando che gli effetti positivi di scarsa volont&agrave; di SIN-1 (10 micromol/L) predominano durante bassa contrattilit&agrave;. Isolated cardiomyocytes murino erano campo stimolato a 1 Hz, e [accorciamento e Ca(2+)](i) transitori sono state registrate. Dopo isoproterenolo sottomassimale (ISO) (agonisti beta-adrenergici, 0,01 micromol/L) stimolazione, 200 micromol/L SIN-1 indotta da due fenomeni distinti. Cardiomyocytes subendo una grande risposta alla ISO ha mostrato una significativa riduzione nella contrattilit&agrave;, mentre cardiomyocytes esibendo una modesta risposta a ISO ha mostrato un ulteriore aumento di contrattilit&agrave;. Inoltre, 10 micromol/L SIN-1 sempre aumentata contrattilit&agrave; durante la stimolazione di ISO bassa, ma non aveva alcun effetto durante la massima stimolazione di ISO (1 micromol/L). SIN-1 a 10 micromol/L anche aumentata contrattilit&agrave; basale. &Egrave; interessante notare che, SIN-1 prodotto un effetto contrattile sotto un&#39;unica condizione nei cardiomyocytes phospholamban-ko, fornendo un meccanismo potenziale per l&#39;effetto bifasico di perossinitrito. Questi risultati forniscono una chiara evidenza di un effetto bifasico di perossinitrito, con alto perossinitrito modulante elevati livelli di beta-adrenergici reattivit&agrave; e basso perossinitrito che regolano la funzione basale e bassi livelli di stimolazione beta-adrenergici.

Effetto bifasico di SIN-1 &egrave; cessante cardiomyocyte stato contrattile.

&#x591A;&#x304F;&#x306E;&#x7814;&#x7A76;&#x304C;&#x30D1;&#x30FC;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x3001;&#x5FC3;&#x7B4B;&#x306E;&#x4E8C;&#x76F8;&#x6027;&#x52B9;&#x679C;&#x3092;&#x5B9F;&#x8A3C;&#x3057;&#x3066;&#x3044;&#x308B;&#x304C;&#x3001;&#x307B;&#x3068;&#x3093;&#x3069;&#x306E;&#x7814;&#x7A76;&#x306F;&#x3053;&#x306E;&#x4E8C;&#x76F8;&#x6027;&#x306B;&#x53CA;&#x307C;&#x3059; &beta;-&#x30A2;&#x30C9;&#x30EC;&#x30CA;&#x30EA;&#x30F3;&#x306E;&#x5FDC;&#x7B54;&#x6027;&#x3068;&#x53CE;&#x7E2E;&#x72B6;&#x614B;&#x4F9D;&#x5B58;&#x6027;&#x3092; &#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x6211;&#x3005; &#x4EE5;&#x524D;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x306B;&#x304A;&#x3051;&#x308B;&#x6975;&#x5927; &beta;-&#x30A2;&#x30C9;&#x30EC;&#x30CA;&#x30EA;&#x30F3;&#x523A;&#x6FC0;&#x306E;&#x9593;&#x306B;&#x6709;&#x610F;&#x306A;&#x4F4E;&#x52B9;&#x679C;&#x306E;&#x9AD8; 3 morpholinosydnonimine &#xFF08;&#x7F6A;-1&#xFF09; &#xFF08;&#x30DA;&#x30EB;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x306E;&#x30BD;&#x30FC;&#x30B9;&#x3001;200 micromol/L&#xFF09; &#x3092;&#x751F;&#x7523;&#x793A;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x73FE;&#x5728;&#x306E;&#x7814;&#x7A76;&#x3067;&#x306F;, &#x4F4E;&#x3044;&#x7F6A; 1 &#xFF08;10 micromol/L&#xFF09; &#x306E;&#x610F;&#x5FD7;&#x306E;&#x30D7;&#x30E9;&#x30B9;&#x52B9;&#x679C;&#x4F4E;&#x53CE;&#x7E2E;&#x4E2D;&#x306B;&#x4E00;&#x4E16;&#x3092;&#x98A8;&#x9761;&#x3057;&#x305F;&#x306B;&#x5BFE;&#x3057;&#x9AD8;&#x7F6A; 1 &#x306E;&#x30DE;&#x30A4;&#x30CA;&#x30B9;&#x306E;&#x52B9;&#x679C;&#x304C;&#x9AD8;&#x306E;&#x53CE;&#x7E2E;&#x72B6;&#x614B;&#x4E2D;&#x306B;&#x6700;&#x5927;&#x306B;&#x306A;&#x308A;&#x307E;&#x3059;&#x3092;&#x4EEE;&#x5B9A;&#x3057;&#x307E;&#x3059;&#x3002;&#x5206;&#x96E2;&#x3055;&#x308C;&#x305F;&#x30DE;&#x30A6;&#x30B9;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x30D5;&#x30A3;&#x30FC;&#x30EB;&#x30C9; 1 Hz &#x3067;&#x523A;&#x6FC0;&#x3055;&#x308C; [&#x3055;&#x305B;&#x305F;&#x30C8;&#x30E9;&#x30F3;&#x30B8;&#x30A7;&#x30F3;&#x30C8;&#x304A;&#x3088;&#x3073;&#x77ED;&#x7E2E;&#x3092;&#x8A18;&#x9332;&#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x6700;&#x5927;&#x4E0B;&#x30A4;&#x30BD;&#x30D7;&#x30ED;&#x30C6;&#x30EC;&#x30CE;&#x30FC;&#x30EB; (ISO) (&beta;-&#x30A2;&#x30C9;&#x30EC;&#x30CA;&#x30EA;&#x30F3;&#x4F5C;&#x52D5;&#x85AC;, 0.01 micromol/L) &#x5F8C;&#x523A;&#x6FC0;, 200 micromol/L &#x7F6A;-1 2 &#x3064;&#x306E;&#x7570;&#x306A;&#x308B;&#x73FE;&#x8C61;&#x3092;&#x8A98;&#x767A;&#x3002;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x306E; ISO &#x3078;&#x306E;&#x3055;&#x3055;&#x3084;&#x304B;&#x306A;&#x5FDC;&#x7B54;&#x3092;&#x5C55;&#x793A;&#x3001;&#x3055;&#x3089;&#x306B;&#x5897;&#x52A0;&#x53CE;&#x7E2E;&#x3092;&#x793A;&#x3057;&#x305F;&#x306B;&#x5BFE;&#x3057; ISO &#x306B;&#x5927;&#x53CD;&#x97FF;&#x3092;&#x53D7;&#x3051;&#x3066;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x53CE;&#x7E2E;&#x6027;&#x306E;&#x5927;&#x5E45;&#x306A;&#x524A;&#x6E1B;&#x3092;&#x793A;&#x3057;&#x305F;&#x3002;&#x3055;&#x3089;&#x306B;&#x3001;10 micromol/L &#x7F6A;-1 &#x306F;&#x5E38;&#x306B;&#x4F4E;&#x306E; ISO &#x523A;&#x6FC0;&#x4E2D;&#x306B;&#x53CE;&#x7E2E;&#x6027;&#x3092;&#x5897;&#x52A0;&#x3057;&#x305F;&#x304C;&#x3001;&#x6700;&#x5927;&#x306E; ISO &#xFF08;1 micromol/L&#xFF09; &#x523A;&#x6FC0;&#x4E2D;&#x306B;&#x306F;&#x52B9;&#x679C;&#x304C;&#x306A;&#x304B;&#x3063;&#x305F;&#x3002;&#x7F6A;-1 10 micromol/L &#x3067;&#x306F;&#x3001;&#x57FA;&#x5E95;&#x306E;&#x53CE;&#x7E2E;&#x6027;&#x3082;&#x5897;&#x52A0;&#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x8208;&#x5473;&#x6DF1;&#x3044;&#x3053;&#x3068;&#x306B;&#x3001;&#x7F6A; 1 &#x53CE;&#x7E2E;&#x52B9;&#x679C;&#x306F; 1 &#x3064;&#x3060;&#x3051;&#x306E;&#x6761;&#x4EF6; phospholamban &#x30CE;&#x30C3;&#x30AF;&#x30A2;&#x30A6;&#x30C8;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x306B;&#x304A;&#x3051;&#x308B;&#x30DA;&#x30EB;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x306E;&#x4E8C;&#x76F8;&#x6027;&#x52B9;&#x679C;&#x306E;&#x305F;&#x3081;&#x306E;&#x6F5C;&#x5728;&#x7684;&#x306A;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x3092;&#x63D0;&#x4F9B;&#x3059;&#x308B;&#x751F;&#x7523;&#x3002;&#x3053;&#x308C;&#x3089;&#x306E;&#x7D50;&#x679C;&#x304B;&#x3089;&#x9AD8;&#x30EC;&#x30D9;&#x30EB;&#x306E; &beta;-&#x30A2;&#x30C9;&#x30EC;&#x30CA;&#x30EA;&#x30F3;&#x306E;&#x5FDC;&#x7B54;&#x6027;&#x3068;&#x57FA;&#x5E95;&#x95A2;&#x6570;&#x304A;&#x3088;&#x3073; &beta;-&#x30A2;&#x30C9;&#x30EC;&#x30CA;&#x30EA;&#x30F3;&#x523A;&#x6FC0;&#x306E;&#x4F4E;&#x30EC;&#x30D9;&#x30EB;&#x3092;&#x898F;&#x5236;&#x3059;&#x308B;&#x4F4E;&#x30D1;&#x30FC;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x5909;&#x8ABF;&#x9AD8;&#x30D1;&#x30FC;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x3068;&#x30DA;&#x30EB;&#x30AA;&#x30AD;&#x30B7; &#x30CA;&#x30A4;&#x30C8; &#x30E9;&#x30A4;&#x30C8;&#x306E;&#x4E8C;&#x76F8;&#x6027;&#x52B9;&#x679C;&#x306E;&#x660E;&#x78BA;&#x306A;&#x8A3C;&#x62E0;&#x3092;&#x63D0;&#x4F9B;&#x3057;&#x307E;&#x3059;&#x3002;

&#x7F6A; 1 &#x306E;&#x4E8C;&#x76F8;&#x6027;&#x52B9;&#x679C;&#x306F;&#x5FC3;&#x7B4B;&#x7D30;&#x80DE;&#x306E;&#x53CE;&#x7E2E;&#x72B6;&#x614B;&#x306B;&#x4F9D;&#x5B58;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;

&#xB9CE;&#xC740; &#xC5F0;&#xAD6C;&#xB294; &#xC2EC;&#xADFC;&#xC5D0;&#xC11C; peroxynitrite&#xC758; &#xB098;&#xC544;&#xC84C;&#xB2E4; &#xD6A8;&#xACFC; &#xC785;&#xC99D; &#xD558;&#xC9C0;&#xB9CC; &#xBA87; &#xC5F0;&#xAD6C; beta-adrenergic &#xC751;&#xB2F5;&#xC5D0;&#xC774; &#xB098;&#xC544;&#xC84C;&#xB2E4; &#xD6A8;&#xACFC; &#xC218;&#xCD95; &#xC0C1;&#xD0DC;&#xC5D0;&#xC758; &#xC758;&#xC874;&#xB3C4; &#xC870;&#xC0AC; &#xD588;&#xC2B5;&#xB2C8;&#xB2E4;. &#xC6B0;&#xB9AC;&#xAC00; &#xC774;&#xC804;&#xC5D0; &#xADF8; &#xB192;&#xC740; 3 morpholinosydnonimine (&#xC8C4;-1) (peroxynitrite&#xC758; &#xC18C;&#xC2A4;, 200 micromol/L) cardiomyocytes&#xC5D0; &#xCD5C;&#xB300;&#xD55C; beta-adrenergic &#xC790;&#xADF9; &#xD558;&#xB294; &#xB3D9;&#xC548; &#xC911;&#xC694; &#xD55C; anti-adrenergic &#xD6A8;&#xACFC; &#xC0DD;&#xC0B0; &#xAC83;&#xC73C;&#xB85C; &#xB098;&#xD0C0;&#xB0AC;&#xC2B5;&#xB2C8;&#xB2E4;. &#xD604;&#xC7AC; &#xC5F0;&#xAD6C;&#xC5D0;&#xC11C; &#xC6B0;&#xB9AC;&#xB294; &#xB0AE;&#xC740; &#xC8C4; 1 (10 micromol/L)&#xC758; &#xC9C0;&#xC758; &#xAE0D;&#xC815;&#xC801;&#xC778; &#xD6A8;&#xACFC; &#xB0AE;&#xC740; &#xC218;&#xCD95; &#xD558;&#xB294; &#xB3D9;&#xC548; &#xC9C0;&#xBC30; &#xD558;&#xB294; &#xBC18;&#xBA74; &#xB192;&#xC740; &#xC8C4;-1&#xC758; &#xBD80;&#xC815;&#xC801;&#xC778; &#xD6A8;&#xACFC; &#xB192;&#xC740; &#xC218;&#xCD95; &#xC0C1;&#xD0DC; &#xC911; &#xAC00;&#xC7A5; &#xD070; &#xC218; &#xAC00;&#xC124;. &#xC808;&#xC5F0;&#xB41C; murine cardiomyocytes &#xD544;&#xB4DC; 1 Hz&#xC5D0;&#xC11C; &#xC790;&#xADF9;&#xB41C; &#xB418;&#xC5C8;&#xACE0; [Ca(2+)](i) &#xACFC;&#xB3C4; &#xBC0F; &#xB2E8;&#xCD95; &#xAE30;&#xB85D; &#xB418;&#xC5C8;&#xB2E4;. Submaximal isoproterenol (ISO) (beta-adrenergic &#xAE38; &#xD56D; &#xC81C;, 0.01 micromol/L) &#xD6C4; &#xC790;&#xADF9;, 200 micromol/L &#xC8C4;-1 &#xB450; &#xAC00;&#xC9C0; &#xD604;&#xC0C1;&#xC744; &#xC720;&#xBC1C; &#xD569;&#xB2C8;&#xB2E4;. Cardiomyocytes iso &#xD070; &#xC751;&#xB2F5;&#xC744; &#xBC1B;&#xC740; &#xBC18;&#xBA74; ISO &#xACB8;&#xC190; &#xD558; &#xAC8C; &#xC751;&#xB2F5; &#xC804;&#xC2DC; cardiomyocytes &#xC218;&#xCD95;&#xC5D0; &#xB354; &#xB192;&#xC544;&#xC84C;&#xC2B5;&#xB2C8;&#xB2E4; &#xC218;&#xCD95;&#xC5D0; &#xC0C1;&#xB2F9;&#xD55C; &#xAC10;&#xC18C;&#xB97C; &#xBCF4;&#xC5EC; &#xC8FC;&#xC5C8;&#xB2E4;. &#xB610;&#xD55C;, micromol/10l &#xC8C4;-1 &#xD56D;&#xC0C1; &#xB0AE;&#xC740; ISO &#xC790;&#xADF9; &#xB3D9;&#xC548; &#xC218;&#xCD95; &#xC99D;&#xAC00; &#xD558;&#xC9C0;&#xB9CC; &#xCD5C;&#xB300; ISO (1 micromol/L) &#xC790;&#xADF9; &#xB3D9;&#xC548; &#xC544;&#xBB34;&#xB7F0; &#xC601;&#xD5A5;&#xC744; &#xBBF8;&#xCE58;&#xC9C0; &#xD588;&#xB2E4;. 10 Micromol/l &#xC8C4;-1&#xC5D0;&#xB294; &#xAE30;&#xC800; &#xC218;&#xCD95; &#xC99D;&#xAC00; &#xD588;&#xB2E4;. &#xD765;&#xBBF8;&#xB86D;&#xAC8C;&#xB3C4;, &#xC8C4;-1 &#xC0DD;&#xC0B0; phospholamban &#xB179;&#xC544;&#xC6C3; cardiomyocytes&#xC5D0; &#xD558;&#xB098;&#xB9CC; &#xC870;&#xAC74;&#xC5D0;&#xC11C; &#xC218;&#xCD95; &#xD6A8;&#xACFC; peroxynitrite &#xB098;&#xC544;&#xC84C;&#xB2E4; &#xD6A8;&#xACFC; &#xB300; &#xD55C; &#xC7A0;&#xC7AC;&#xC801;&#xC778; &#xBA54;&#xCEE4;&#xB2C8;&#xC998;&#xC744; &#xC81C;&#xACF5; &#xD558;. &#xC774;&#xB7EC;&#xD55C; &#xACB0;&#xACFC; beta-adrenergic &#xC751;&#xB2F5; &#xC18D;&#xB3C4; &#xB0AE;&#xC740; peroxynitrite &#xAE30;&#xC800; &#xD568;&#xC218; &#xBC0F; beta-adrenergic &#xC790;&#xADF9; &#xB0AE;&#xC740; &#xC218;&#xC900;&#xC758; &#xADDC;&#xC81C;&#xC758; &#xC0C1;&#xBD80;&#xB97C; &#xBCC0;&#xC870; &#xD558;&#xB294; &#xB192;&#xC740; peroxynitrite&#xC640; peroxynitrite&#xC758; &#xB098;&#xC544;&#xC84C;&#xB2E4; &#xD6A8;&#xACFC; &#xB300; &#xD55C; &#xBA85;&#xBC31;&#xD55C; &#xC99D;&#xAC70;&#xB97C; &#xC81C;&#xACF5;.

&#xC8C4; 1 &#xB098;&#xC544;&#xC84C;&#xB2E4; &#xD6A8;&#xACFC; cardiomyocyte &#xC218;&#xCD95; &#xC0C1;&#xD0DC;&#xC5D0; &#xB530;&#xB77C; &#xC758;&#xC874; &#xD569;&#xB2C8;&#xB2E4;.

Muchos estudios han demostrado un efecto bif&aacute;sico de peroxinitrito en el miocardio, pero pocos estudios han investigado este efecto bif&aacute;sico en respuesta beta-adren&eacute;rgico y su dependencia del estado contr&aacute;ctil. Hemos demostrado previamente que alta 3-morpholinosydnonimine (SIN-1) (fuente de peroxinitrito, 200 micromol/L) producido efectos significativos adren&eacute;rgico durante la m&aacute;xima estimulaci&oacute;n beta-adren&eacute;rgico en los cardiomiocitos. En el estudio actual, presumimos que los efectos negativos de alto SIN-1 ser&aacute; mayores durante los Estados contr&aacute;ctiles altos, mientras que los efectos positivos de la baja voluntad de pecado-1 (10 micromol/L) predominan durante la contractilidad baja. Cardiomiocitos murinos aislados fueron estimulado a 1 Hz de campo, y [acortamiento y Ca(2+)](i) transitorios fueron registrados. Despu&eacute;s subm&aacute;ximo isoproterenol (ISO) (agonista beta-adren&eacute;rgico, 0.01 micromol/L) estimulaci&oacute;n, 200 micromol/L pecado-1 inducida por dos fen&oacute;menos distintos. Cardiomiocitos sometidos a una gran respuesta a ISO mostraron una reducci&oacute;n significativa en la contractilidad, mientras que cardiomiocitos exhibiendo una modesta respuesta a ISO demostraron un aumento en la contractilidad. Adem&aacute;s, 10 micromol/L pecado-1 siempre aument&oacute; contractilidad durante estimulaci&oacute;n de ISO baja, pero no tuvo ning&uacute;n efecto durante la m&aacute;xima estimulaci&oacute;n de ISO (1 micromol/L). PECADO-1 en 10 micromol/L tambi&eacute;n aument&oacute; la contractilidad basal. Curiosamente, SIN-1 produjo un efecto contr&aacute;ctil bajo la sola condici&oacute;n en cardiomiocitos fosfolamdano-octavos de final, proporcionando un mecanismo potencial para el efecto bif&aacute;sico de peroxinitrito. Estos resultados proporcionan evidencia clara de un efecto bif&aacute;sico de peroxinitrito, con alta peroxinitrito modulaci&oacute;n altos niveles de respuesta beta-adren&eacute;rgico y peroxinitrito baja regulaci&oacute;n de la funci&oacute;n basal y bajos niveles de estimulaci&oacute;n beta-adren&eacute;rgico.

Efecto bif&aacute;sico de pecado-1 es dependiente de estado contr&aacute;ctil cardiomiocitos.

Modulation of purinergic signaling is critical to myocardial homeostasis. Ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) which converts the proinflammatory molecules ATP or ADP to AMP is a key regulator of purinergic modulation. However, the salutary effects of transgenic over expression of ENTPD-1 on myocardial response to ischemic injury have not been tested to date. Therefore we hypothesized that ENTPD-1 over expression affords myocardial protection from ischemia-reperfusion injury via specific cell signaling pathways. ENTPD-1 transgenic mice, which over express human ENTPDase-1, and wild-type (WT) littermates were subjected to either ex vivo or in vivo ischemia-reperfusion injury. Infarct size, inflammatory cell infiltrate and intracellular signaling molecule activation were evaluated. Infarct size was significantly reduced in ENTPD-1 versus WT hearts in both ex vivo and in vivo studies. Following ischemia-reperfusion injury, ENTPD-1 cardiac tissues demonstrated an increase in the phosphorylation of the cellular signaling molecule extracellular signal-regulated kinases 1/2 (ERK 1/2) and glycogen synthase kinase-3β (GSK-3β). Resistance to myocardial injury was abrogated by treatment with a non-selective adenosine receptor antagonist, 8-SPT or the more selective A(2B) adenosine receptor antagonist, MRS 1754, but not the A(1) selective antagonists, DPCPX. Additionally, treatment with the ERK 1/2 inhibitor PD98059 or the mitochondrial permeability transition pore opener, atractyloside, abrogated the cardiac protection provided by ENTPDase-1 expression. These results suggest that transgenic ENTPDase-1 expression preferentially conveys myocardial protection from ischemic injury via adenosine A(2B) receptor engagement and associated phosphorylation of the cellular protective signaling molecules, Akt, ERK 1/2 and GSK-3β that prevents detrimental opening of the mitochondrial permeability transition pore.

Transgenic over expression of ectonucleotide triphosphate diphosphohydrolase-1 protects against murine myocardial ischemic injury.

CD39 (ectonucleoside triphosphate diphosphohydrolase-1; ENTPD-1) rapidly hydrolyzes ATP and ADP to AMP; AMP is hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine, an anti-thrombotic and cardiovascular protective mediator. While expression of human CD39 in a murine model of myocardial ischemia/reperfusion (I/R) injury confers cardiac protection, the translational therapeutic potential of these findings requires further testing in a large animal model. To determine if transgenic expression of CD39 reduces infarct size in a swine model of myocardial ischemia/reperfusion injury, transgenic pigs expressing human CD39 (hCD39) were generated via somatic cell nuclear transfer and characterized. Expression of hC39 in cardiac tissue was confirmed by immunoblot and immunohistochemistry. Myocardial I/R injury was induced by intracoronary balloon inflation in the left anterior descending (LAD) artery for 60 min followed by 3 hours of reperfusion. The ischemic area was delineated by perfusion with 5% phthalo blue and the myocardial infarct size was determined by triphenyl tetrazolium chloride (TTC) staining. During ischemia, the rate-pressure product was significantly lower in control versus hCD39-Tg swine. Following reperfusion, compared to littermate control swine, hCD39-Tg animals displayed a significant reduction in infarct size (hCD39-Tg: 17.2 ± 4.3% vs.

Transgenic swine: expression of human CD39 protects against myocardial injury.

Modulation of purinergic signaling, which is critical for vascular homeostasis and the response to vascular injury, is regulated by hydrolysis of proinflammatory ATP and/or ADP by ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) to AMP, which then is hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine. We report here that compared with littermate controls (wild type), transgenic mice expressing human ENTPDase-1 were resistant to the formation of an occlusive thrombus after FeCl(3)-induced carotid artery injury. Treatment of mice with the nonhydrolyzable ADP analog, adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S], negated the protection from thrombosis, consistent with a role for ADP in platelet recruitment and thrombus formation. ENTPD-1 expression decreased whole-blood aggregation after stimulation by ADP, an effect negated by adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S] stimulation, and limited the ability to maintain the platelet fibrinogen receptor, glycoprotein α(IIb)/β(3), in a fully activated state, which is critical for thrombus formation. In vivo treatment with a CD73 antagonist, a nonselective adenosine-receptor antagonist, or a selective A(2A) or A(2B) adenosine-receptor antagonist, negated the resistance to thrombosis in transgenic mice expressing human ENTPD-1, suggesting a role for adenosine generation and engagement of adenosine receptors in conferring in vivo resistance to occlusive thrombosis in this model. In summary, our findings identify ENTPDase-1 modulation of purinergic signaling as a key determinant of the formation of an occlusive thrombus after vascular injury.

Ectonucleotide triphosphate diphosphohydrolase-1 (CD39) mediates resistance to occlusive arterial thrombus formation after vascular injury in mice.

Circulating blood cells and endothelial cells express ectonucleoside triphosphate diphosphohydrolase-1 (CD39) and ecto-5'-nucleotidase (CD73). CD39 hydrolyzes extracellular ATP or ADP to AMP. CD73 hydrolyzes AMP to adenosine. The goal of this study was to examine the interplay between CD39 and CD73 cascade in arterial thrombosis.

Role of the CD39/CD73 Purinergic Pathway in Modulating Arterial Thrombosis in Mice.

Prior work suggests that ischemic preconditioning increases the level of CD39 in the heart and contributes to cardiac protection. Therefore, we examined if targeted cardiac expression of CD39 protects against myocardial injury.

Impact of cardiac-specific expression of CD39 on myocardial infarct size in mice.

Despite increased secondary cardiovascular events in patients with ischemic cardiomyopathy (ICM), the expression of innate cardiac protective molecules in the hearts of patients with ICM is incompletely characterized. Therefore, we used a nonbiased RNAseq approach to determine whether differences in cardiac protective molecules occur with ICM.

 Ablation Is Associated With Increased Nitro-Oxidative Stress During Ischemia-Reperfusion Injury: Implications for Human Ischemic Cardiomyopathy.

Endothelial surface and circulating glycoprotein von Willebrand factor (vWF) regulates platelet adhesion and is associated with thrombotic diseases, including ischemic stroke, myocardial infarction, and peripheral vascular disease. Thrombosis, as manifested in these diseases, is the leading cause of disability and death in the western world. Current parenteral antithrombotic and thrombolytic agents used to treat these conditions are limited by a short therapeutic window, irreversibility, and major risk of hemorrhage. To overcome these limitations, we developed a novel anti-vWF aptamer, called DTRI-031, that selectively binds and inhibits vWF-mediated platelet adhesion and arterial thrombosis while enabling rapid reversal of this antiplatelet activity by an antidote oligonucleotide (AO). Aptamer DTRI-031 exerts dose-dependent inhibition of platelet aggregation and thrombosis in whole blood and mice, respectively. Moreover, DTRI-031 can achieve potent vascular recanalization of platelet-rich thrombotic occlusions in murine and canine carotid arteries. Finally, DTRI-031 activity is rapidly (<5 min) and completely reversed by AO administration in a murine saphenous vein hemorrhage model, and murine toxicology studies indicate the aptamer is well tolerated. These findings suggest that targeting vWF with an antidote-controllable aptamer potentially represents an effective and safer treatment for thrombosis patients having platelet-rich arterial occlusions in the brain, heart, or periphery.

ArticleTotal : 2	Year
Publication title Cited by 9	2018
Publication title Cited by 7	2020

Article	Year
Effect of glutathione augmentation on lipid peroxidation after spinal cord injury. Journal of neurotrauma\| PubMed ID: 12165136	2002
Targeting of phospholamban by peroxynitrite decreases beta-adrenergic stimulation in cardiomyocytes. Cardiovascular research\| PubMed ID: 18006474	2008
Endothelial nitric oxide synthase decreases beta-adrenergic responsiveness via inhibition of the L-type Ca2+ current. American journal of physiology. Heart and circulatory physiology\| PubMed ID: 18203845	2008
Neuronal nitric oxide synthase signaling within cardiac myocytes targets phospholamban. American journal of physiology. Cell physiology\| PubMed ID: 18400986	2008
Biphasic effect of SIN-1 is reliant upon cardiomyocyte contractile state. Free radical biology & medicine\| PubMed ID: 18433725	2008
Transgenic over expression of ectonucleotide triphosphate diphosphohydrolase-1 protects against murine myocardial ischemic injury. Journal of molecular and cellular cardiology\| PubMed ID: 21939667	2011
Transgenic swine: expression of human CD39 protects against myocardial injury. Journal of molecular and cellular cardiology\| PubMed ID: 22269791	2012
Ectonucleotide triphosphate diphosphohydrolase-1 (CD39) mediates resistance to occlusive arterial thrombus formation after vascular injury in mice. The American journal of pathology\| PubMed ID: 22613024	2012
Role of the CD39/CD73 Purinergic Pathway in Modulating Arterial Thrombosis in Mice. Arteriosclerosis, thrombosis, and vascular biology\| PubMed ID: 27417582	2016
Impact of cardiac-specific expression of CD39 on myocardial infarct size in mice. Life sciences\| PubMed ID: 27756600	2017
Ablation Is Associated With Increased Nitro-Oxidative Stress During Ischemia-Reperfusion Injury: Implications for Human Ischemic Cardiomyopathy. Circulation. Heart failure\| PubMed ID: 28209764	2017
Preclinical Development of a vWF Aptamer to Limit Thrombosis and Engender Arterial Recanalization of Occluded Vessels. Molecular therapy : the journal of the American Society of Gene Therapy\| PubMed ID: 30987839	2019

Debra G. Wheeler

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