Name: Photothrombosis-induced Focal Ischemia as a Model of Spinal Cord Injury in Mice (Video) | JoVE Journal
Uploaded: 2015-07-16T15:00:00.000+00:00
Duration: 8 min 27 s
Description: Learn photothrombosis-induced focal ischemia to model spinal cord injury in mice. This reproducible method uses surgical exposure, dye administration, and vessel irradiation to study injury mechanisms and test neuroprotective therapies.

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5 minutes

This work was supported by the National Institutes of Health [Grant no. R01NS069726] and the American Heart Association Grant in Aid Grant [Grant no. 13GRNT17020004] to SD.

Note: Mice (C57BL/6J, male) aged 10 &#8211; 12 weeks were used in this study. All the procedures were performed in accordance with the NIH Guide for the Care and Use of Laboratory Animals and were approved by the University of Missouri Institutional Animal Care and Use Committee (IACUC).&#160;
1. Pre-Surgery
<ol>
	<li>The day before surgery autoclave and sterilize all the surgical instruments. Wrap the instruments and autoclave at 121 oC at 15 psi for 30 min followed by 30 min of drying (121 oC, 15 psi, 30/30 cycle). Place the instruments in a clean and sterile environment until further use.</li>
	<li>Prepare fresh Rose Bengal (RB) solution (20 mg/ml in sterile saline) every time before the surgery. To completely dissolve RB, vortex the tube then followed by sonication for 5 min at 50/60 Hz with output power of 19 W. Wrap the tube in aluminum foil and protect it from light until further used during surgery.</li>
	<li>Prepare a mixture of ketamine/xylazine in sterile saline. Add 125 &#181;l of xylazine (stock concentration: 20 mg/ml) and 325 &#181;l of ketmaine (stock concentration: 100 mg/ml) and 550 &#181;l of sterile saline to make a final volume of 1 ml of anesthetic mixture.</li>
	<li>Pre-warm the homeothermic heating pad.</li>
	<li>Pre-warm the metal halide lamp (light source for FN1 epi-fluorescence microscope) for 30 min to stabilize the lamp power.</li>
	<li>Adjust the size of the illuminated region to a diameter of 1 mm using 10X objective and a reticle by adjusting the field diaphragm in the upright FN1 epi-fluorescence microscope.</li>
</ol>
2. Surgical Procedure
<ol>
	<li>Anesthetize the mouse with a dose of ketamine (130 mg/kg B. wt.) and xylazine (10 mg/kg B. wt.). Based on the cocktail in 1.3,&#160; 4 &#181;l per g of mouse B. wt. are needed. Sterilize the site of injection with an alcohol swab and administer the anesthetics through the intra-peritoneal (IP) route. Take care not to inject the anesthetics into the blood vessels or muscle as this would delay the induction and recovery of the animal.</li>
	<li>Apply artificial tear ointment to both eyes of the mouse to prevent drying and place the animal on the heating pad to prevent hypothermia.</li>
	<li>Preparation of animal
	<ol>
		<li>Check the animal for proper surgical level anesthesia by using the toe pinch response.</li>
		<li>Once the animal has reached surgical level of anesthesia, clip the hair on the dorsal surface around midline of the animal using an electric hair trimmer. Scrub the surgical site with 70% ethanol followed by betadine solution three times. Cover the site with a sterile surgical drape until next step.</li>
	</ol>
	</li>
	<li>Surgical procedure to thin the bone to expose the spinal cord
	<ol>
		<li>Place the mouse in a prone position over the homeothermic heating pad on the surgical platform (Figure 1A). Properly secure the mouse posture using a snout clamp to maintain an elongated neck region (Figure 1A, B).</li>
		<li>Make an incision (approximately 1 cm long) using surgical scissors along the dorsal mid line extending from the thoracic vertebrae T9 to T12. Move aside the skin to expose surgical area.</li>
		<li>Using a scalpel, carefully clear the muscle to expose the dorsal spines at T9 - T12 vertebrae. Stop bleeding in each step by applying gentle pressure with sterile cotton swab. Separate T10 - T12 vertebrae from the surrounding muscle and secure them using a vertebral clamp to stabilize and prevent any movement (Figure 1A, B).</li>
		<li>Using a high speed drill with bone polishing drill bit, carefully and gently thin the dorsal surface of T10 or T11 vertebra to visualize the posterior spinal vein and other small vessels on the dorsal surface of the SC (Figure 1C).</li>
		<li>To prevent thermal damage due to heat generated during the thinning procedure, apply a gentle and constant stream of normal saline along with constant suction to remove the debris.</li>
		<li>Using a scalpel carefully smooth the bone surface until the main vessel is clearly visible. Take care not to damage the spinal cord during this process.</li>
		<li>Once the blood vessel is visualized, administer RB at a dose of 30 mg/kg (body weight) through retro-orbital sinus route using an insulin syringe.</li>
		<li>Measure blood flow using a Laser Doppler flowmeter after 3 min following RB injection if necessary (Figure 2A, B). Maintain asepsis during entire procedure.</li>
	</ol>
	</li>
</ol>
3. Induction of PT
<ol>
	<li>Place the animal on an X-Y position adjustable stage over a Lab-Jack which can adjust the height. Adjust the position of the mouse so the exposed region of T11 spinal cord is directly under the 10x objective of the FN1 epi-fluorescence microscope (Figure 3A).</li>
	<li>Set the power of the light source at 12% and irradiate the T11 region with a diameter of 0.75 mm in the middle of thinned spinal cord (Note: this region includes the posterior spinal vein and other capillaries) with a green light (wavelength 540 - 580 nm, which is achieved by the filter cube in the microscope) through the 10X objective for 2 min. Take images at the beginning and end of irradiation (Figure 3B, C) and record the time of the experiment at this point.</li>
	<li>Measure blood flow again for 10 min if necessary by placing the laser Doppler probe to the same position above the spinal cord as in 2.4.8 (Figure 2A, B).</li>
	<li>After irradiation check for any hemorrhage and if none found proceed to suturing the animal. Suture the superficial fascia along with the muscles on the either side of spinal cord using an absorbable suture or&#160;4-0 size silk&#160;suture. Take care not to damage the exposed SC. Suture the skin with 4-0 silk suture. Apply Betadine or iodine to the edges of the skin after suturing.</li>
</ol>
4. Post-surgery Care
<ol>
	<li>After suturing, place the animal on the heating pad for recovery. After recovery check the animals for signs of neurological deficits by observing the movement of both hind-limbs. Do not leave the animal unattended until it has regained sufficient consciousness to maintain sternal recumbency.</li>
	<li>Transfer the animals to the home cage. Do not return the animal that has undergone surgery to the company of other animals until fully recovered.</li>
	<li>Check the animals at regular intervals. In case of severe neurological deficits, provide proper care like evacuation of bladder, administration of analgesics (buprenorphine, 0.05 - 0.1 mg/kg). Check for dehydration and administer normal saline subcutaneously in severe case.&#160;Usually, buprenorphine ( 0.1 mg/kg) will be administered after suturing to relieve pain in the surgical site.</li>
	<li>If animals are not immediately euthanized after surgery, we will put high water content diet on the cage floor, so the animals can reach the food easily.</li>
</ol>
5. Transcardial Perfusion, Nissl staining and Immunostaining
<ol>
	<li>Transcardially perfuse the animal as described previously17-20.
	<ol>
		<li>Anesthetize the animal as described earlier in the protocol and transcardially perfuse with phosphate buffer saline (PBS, pH 7.4), followed by ice-cold 4% paraformaldehyde (PFA) in PBS.</li>
		<li>After perfusion, remove the spinal cord (SC) and post-fix it in 4% PFA in PBS at 4 &#176;C O/N. Transfer the fixed SC into PBS with 30% sucrose and keep it for 2 - 3 days until it sinks to the bottom of the tube.</li>
		<li>Using a cryostat cut the spinal cord into 30 &#181;m thick sections and place them serially on a gelatin-coated glass slides or in a 48-well plate with 0.01 M PBS.</li>
	</ol>
	</li>
	<li>Nissl staining: To inspect the injury caused by PT perform a Nissl staining on spinal cord sections as previously described17-20.
	<ol>
		<li>Briefly, collect every fifth spinal cord slice on the glass slides and stain with 0.25% cresyl violet. Take images of the stained sections (Figure 4).</li>
	</ol>
	</li>
	<li>Immunostaining: As described previously using a floating section method17,18,20.
	<ol>
		<li>Briefly, stain the spinal cord sections by incubating O/N at 4 &#176;C with rabbit anti-glia fibrillary acidic protein (GFAP) polyclonal antibody (1:300), rabbit anti-NeuN antibody (1:300), and rabbit anti-Iba1 antibody (1:500) followed by donkey anti rabbit Alexa 568-conjugated IgG (1:400) secondary antibodies for 4 h at RT. Take images with a fluorescent microscope (Figure 5).</li>
	</ol>
	</li>
</ol>

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</ol>

The authors have nothing to disclose.

In this study, we described a photothrombotic model of SC ischemia. Due to advances in genetic engineering there has been a surge in commercially available transgenic mice which has made it possible to study the impact of specific genes involved in the ischemic pathophysiology in the SC. The aim of the study was to develop a reproducible mouse model of spinal cord ischemia. Here we adapted a cortical PT model to induce SCI in mice. Following surgery the posterior spinal vein and capillaries on the dorsal...

Traumatic spinal cord injury (SCI) is a devastating clinical condition affecting the sensorimotor and autonomic functions of the SC. Patients surviving SCI are often left with debilitating paraplegia that significantly affects their daily activities and quality of life1. Experimental SCI models have been an indispensable tool in the scientific investigation to understand the pathophysiology of SCI and associated neural repair processes. These models have also been used to test the preclinical efficacy of various experimental neuroprotective interventions that are aimed at functional recovery. Currently, majority of the SCI models in practice employ the use of physical blunt force to mechanically disrupt and injure the SC. These methods include contusion, compression, dislocation and transection of the SC2. It has been suggested that after the primary mechanical insult a secondary injury in the form of ischemia sets in in the injured SC3,4. The etiology of secondary ischemia includes extensive tissue degeneration, parenchymal hemorrhage and sometimes by obstruction of blood vessels by tissue edema5-7. As a result of the secondary injury the integrity of SC is further affected, neurons and glial cells are severely impaired in function and viability and undergo apoptosis which leads to infarct growth during the chronic stage of injury, analogous to the growth of ischemic penumbra following stroke8,9. Several mechanisms like excitotoxicity, free radical production, and inflammation have been reported to be responsible for the ischemic cell death following SCI10,11. In addition, SC ischemia is a serious complication of thoraco-abdominal aortic aneurysm repair surgeries which often lead to paraplegia in the patients12,13. In spite of such high clinical impact very few models of spinal cord ischemia with high reproducibility are currently available.
Photothrombosis (PT) is a commonly used method for the induction of focal ischemia in the brain14-20. The technique is fairly non-invasive, highly reproducible and produces a precise focal ischemic lesion in the exposed area of the brain17-21. This is achieved by systemic administration of photoactive dyes like Rose Bengal (RB)16-20,22 or erythrosine B23 followed by localized irradiation of blood vessels with proper light source. Photoactivation of the dye causes the generation of free radicals which disrupt the integrity of the smooth vascular endothelium, and cause the platelets to accumulate, which subsequently forms a thrombus. The obstruction of blood flow by the thrombus results in an infarct in the region supplied by the vessel24. Due to ease of control on the intensity and duration of irradiation this procedure yields a highly uniform and reproducible infarct. Furthermore, this method can be employed to induce an infarct at various anatomical locations enabling spatial (e.g., grey matter vs. white matter) understanding of the effect of ischemia.
The aim of the current study is to develop an easy and highly reproducible model of SC ischemia in mice. We described the procedure of a PT model of SC ischemia in mice. Results from histology and immunostaining demonstrated that PT can effectively induce SC infarction, neuronal loss and reactive gliosis.

<table><tbody><tr><td>Rose Bengal</td><td>Sigma-Aldrich</td><td>330000</td><td>20 mg/ml in sterile saline</td></tr><tr><td>C57BL/6J</td><td>Jackson lab</td><td>664</td><td>22 - 25 g</td></tr><tr><td>Ketamine&amp;nbsp;</td><td>VEDCO</td><td>NDC-50989-996-06</td><td>100 mg/ml</td></tr><tr><td>Xylazine&amp;nbsp;</td><td>VEDCO</td><td>NDC-50989-234-11</td><td>100 mg/ml</td></tr><tr><td>Betadine solution</td><td>Purdue</td><td>NDC-67618-150-01</td><td>10% povidone iodine topical solution</td></tr><tr><td>Normal saline</td><td>Abott Laboratories</td><td>04930-04-10</td><td>For diluting RB, anaesthesia and for preventing tissue from drying</td></tr><tr><td>Artificial tears ointment&amp;nbsp;</td><td>Rugby</td><td>NDC-0536-6550-91</td><td>83% white petrolatum</td></tr><tr><td>Ethanol</td><td>Decon labs.Inc</td><td>2716</td><td>70% ethanol for disinfection</td></tr><tr><td>Metal halide lamp</td><td>EXFO, Canada</td><td>X-Cite 120 PC&amp;nbsp;</td><td>Set power at 12%</td></tr><tr><td>Spring scissors&amp;nbsp;</td><td>Fine Science Tool</td><td>15000-10</td><td>for minor dissection</td></tr><tr><td>Scissors (angled to side)</td><td>Fine Science Tool</td><td>14063-011</td><td>No. 3 handle</td></tr><tr><td>Standard scalpel</td><td>Fine Science Tool</td><td>10003-12</td><td>for removing muscle</td></tr><tr><td>Scalpel blade</td><td>Feather</td><td>2976</td><td>No. 10</td></tr><tr><td>Forceps (curved)</td><td>Fine Science Tool</td><td>11150-10</td><td>for holding tissue</td></tr><tr><td>Forceps (straight)</td><td>Fine Science Tool</td><td>11151-10</td><td>for holding tissue</td></tr><tr><td>Needle holder&amp;nbsp;</td><td>Fine Science Tool</td><td>12002-12</td><td>for suturing</td></tr><tr><td>Tissue adhesive glue</td><td>3M Vetbond</td><td>1469SB</td><td>to adhere to edges of the cut skin</td></tr><tr><td>Monofilament polypropylene&amp;nbsp;</td><td>USSC Sutures</td><td>VP-521</td><td>Size = 4-0 (for fascia)</td></tr><tr><td>Perma-hand silk</td><td>Ethicon</td><td>683G</td><td>Size = 4-0 (for skin)</td></tr><tr><td>Micro drill</td><td>Roboz Surgical Instrument Co. Inc.</td><td>RS-6300</td><td>with bone polishing drill bit</td></tr><tr><td>Laser doppler flowmeter</td><td>Moor Instruments</td><td>moorVMS-LDF1</td><td>for monitoring change in blood flow</td></tr><tr><td>Heating pad</td><td>Fine Science Tool</td><td>21052-00</td><td>to prevent hypothermia</td></tr><tr><td>Lab-Jack</td><td>Fisher scientific&amp;nbsp;</td><td>14-673-50</td><td>4 x 4 in plate to adjust the height of the animal</td></tr><tr><td>X-Y gliding stage&amp;nbsp;</td><td>Amscope</td><td>GT100</td><td>for positioning the animal under microscope&amp;nbsp;&amp;nbsp;</td></tr></tbody></table>

photothrombosis-induced focal ischemia as a model of spinal cord injury in mice

Photothrombosis-induced Focal Ischemia as a Model of Spinal Cord Injury in Mice

Spinal cord injury (SCI) is a devastating clinical condition causing permanent changes in sensorimotor and autonomic functions of the spinal cord (SC) below the site of injury. The secondary ischemia that develops following the initial mechanical insult is a serious complication of the SCI and severely impairs the function and viability of surviving neuronal and non-neuronal cells in the SC. In addition, ischemia is also responsible for the growth of lesion during chronic phase of injury and interferes with the cellular repair and healing processes. Thus there is a need to develop a spinal cord ischemia model for studying the mechanisms of ischemia-induced pathology. Focal ischemia induced by photothrombosis (PT) is a minimally invasive and very well established procedure used to investigate the pathology of ischemia-induced cell death in the brain. Here, we describe the use of PT to induce an ischemic lesion in the spinal cord of mice. Following retro-orbital sinus injection of Rose Bengal, the posterior spinal vein and other capillaries on the dorsal surface of SC were irradiated with a green light resulting in the formation of a thrombus and thus ischemia in the affected region. Results from histology and immunochemistry studies show that PT-induced ischemia caused spinal cord infarction, loss of neurons and reactive gliosis. Using this technique a highly reproducible and relatively easy model of SCI in mice can be achieved that would serve the purpose of scientific investigations into the mechanisms of ischemia induced cell death as well as the efficacy of neuroprotective drugs. This model will also allow exploration of the pathological changes that occur following SCI in live mice like axonal degeneration and regeneration, neuronal and astrocytic Ca2+ signaling using two-photon microscopy.

The aim of this study was to produce spinal cord ischemia in mice using a PT model. After the desired region of bone above the spinal cord (T10 - T12) was thinned, Rose Bengal was injected through retro-orbital sinus route, and ischemia was induced by PT. Figure 1A, B show the mouse positioned in a custom-made surgical platform during surgery. The mouse was held in place by a snout clamp and two adjustable vertebrate clamps to stabilize the spinal cord. Figure 1C show a thinned window ab...

Photothrombosis is a minimally invasive and highly reproducible procedure to induce focal ischemia in the spinal cord and serves as a model of spinal cord injury in mice.

Spinal cord injury (SCI) is a devastating clinical condition causing permanent changes in sensorimotor and autonomic functions of the spinal cord (SC) ...

The overall goal of this procedure is to develop an easy and highly reproducible model of spinal cord ischemia in mice. This is accomplished by first surgically dissecting the dorsal surface of the mouse to expose the T nine through T 12 vertebrae. In the second step, a high speed drill is used to thin the dorsal surface of the T 10 or T 11 vertebrae exposing the posterior spinal vessels.A photo active dye is then administered via the retroorbital root to label the blood vessels. In the final step, the posterior spinal vessels on the dorsal surface of the spinal cord are irradiated to induce photo thrombosis in the exposed blood vessel. Ultimately, the outcome of the spinal cord injury is assessed by nissle, staining and immunohistochemistry.The implications of this technique extend toward therapy of spinal cord ischemia as it can be used to test the efficacy of various neuroprotective drugs aimed at improving cell survival and recovery after spinal cord injury. Demonstrating the procedure will be Nana, a research scholar myself, ri both from dr. She's lab.Before beginning the surgery, prewarm the metal allied lamp for 30 minutes to stabilize the lamp power. Then using the 10 x objective and theoretical, adjust the field diaphragm in an upright FN one epi fluorescence microscope to set the size of the illuminated region to 0.75 millimeter diameter. Next, apply artificial tear ointment to both eyes of an anesthetized mouse and place the animal onto a prewarm heating pad.Confirm the appropriate state of anesthesia by a lack of response to toe pinch. Then use an electric hair trimmer to clip the hair on the animal's dorsal surface around the midline. Scrub the surgical site with 70%ethanol, followed by Betadine solution three times, and then drape the animal.Now, place the animal in the prone position on a homeo themic heating pad on a surgical platform using a snout clamp to secure the animal and to maintain an elongated neck region. Then begin the surgery by making an incision along the dorsal midline from the T nine to the T 12 thoracic vertebrae. Moving aside the skin to expose the surgical area using a scalpel, carefully clear the muscle to expose the dorsal spines of the T nine through T 12 vertebrae, stopping the bleeding as necessary with the gentle application of a sterile cotton swab.Next, separate the T 10 through T 12 vertebrae from the surrounding muscle and secure them with a vertebral clamp to stabilize the animal and to prevent any movement using a high speed drill equipped with a bone polishing drill bit. Now, carefully and gently thin the dorsal surface of the T 10 or T 11 vertebra to visualize the posterior spinal vein and other small vessels on the dorsal surface of the spinal cord. Take care during this step as excess pressure might cause the drill to enter into the spinal cavity and damage spinal cord, while uneven thinning of the bone may result in improper elimination and production of irregular infarc.To prevent thermal damage during the thinning procedure, apply a gentle and constant stream of normal saline along with constant suction to remove the debris. Then using a scalpel, carefully smooth the bone surface until the main vessel is clearly visible. Taking care not to damage the spinal cord.Once the blood vessel is visible, use an insulin syringe to administer the photo active dye through the retroorbital sinus. Three minutes after the injection, measure the blood flow with a laser doppler flow meter to induce photo thrombosis. Place the animal on an XY position, adjustable stage over a height adjustable lab jack moving the mouse until the exposed region of the spinal cord is directly under the 10 x objective of the microscope.Set the power of the light source to 12%and irradiate the exposed region in the middle of the thinned spinal cord through the 10 x objective for two minutes. Obtain images at the beginning and the end of irradiation recording the time of each image capture. If no hemorrhaging is observed, use an absorbable four oh size suture to close the superficial fascia along with the muscles on either side of the spinal cord, followed by closure of the skin with the same, then apply antiseptic to the edges of the skin and place the animal back onto the heating pad.When the animal has fully recovered. Check for signs of neurological deficits by observing the movement of both hind limbs to confirm the induction of ischemia. Changes in the blood flow can be measured with a laser doppler flow meter before and after photo thrombosis.As just demonstrated in this experiment, the blood flow dropped to about 20%immediately after the light illumination compared to the basal level here, fluorescent images of the spinal cord blood vessels at the beginning and end of the photo thrombosis are shown. Note the formation of a blood clot after the two minute photo period suggesting the induction of ischemia and consistent with the reduced blood flow measured by the laser doppler flow meter. In this series of rostral toco spinal cord transverse sections of a normal and photo thrombosis induced epicenters three days after photo thrombosis, a clearly demarcated infarct region indicating the presence of spinal cord tissue damage and cell death in the photo illuminated tissues can be observed.Indeed, immuno staining of the spinal cord tissue three days after thrombosis revealed a loss of new end positive neurons in the gray matter of the ischemic core. While the GFAP expression was increased in the ischemic core border, the IBA one positive microglia also exhibited a G OID morphology, as well as an increased IBA one expression with an overall increase in the GFAP and IBA one expression in the entire per infarct region indicating neuronal death and reactive gliosis in the penumbra after spinal cord ischemia. Further substantial functional deficits such as disabled hind limb movement one day after photo thrombosis were also observed in the injured animals.Following this procedure, a methods like two photo microscopic can be performed to answer additional questions like, what are the roles of axonal degeneration, regeneration, and neuronal acetic calcium signaling in spinal cord ischemia? After watching this video, you should have a good understanding of how to thin the dorsal surface of T 10 RT 11 vertebrae, and how to eradiate the exposed posterior spinal blood vessels.

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This video demonstrates the procedure to generate photothrombotic stroke in a mouse model by laser illumination of an intact skull following administration of photosensitive dye.

Modeling Photothrombotic Stroke in Mouse Model: A Laser Illumination Technique Through Mouse Skull Following Photosensitive Dye Administration to Induce Photothrombosis

Source: Elzat, E. Y. Y., et al., Establishing a Mouse Contusion Spinal Cord Injury Model Based on a Minimally Invasive Technique. J. Vis. Exp. (2022).This video demonstrates the method for inducing a contusion injury at the T9 level spinal cord in a mouse model, using a spinal cord injury coaxial platform. A weight is dropped on the T9 level spinal cord that creates a contusion that immediately causes tissue discoloration and swelling.

Inducing a Spinal Cord Contusion in a Mouse Model Using a Spinal Cord Injury Coaxial Platform

Photothrombosis is a quick, minimally-invasive technique for inducing small and well-delimited infarction in areas of interest in highly reproducible manner. It is particularly suitable for studying cellular and molecular responses underlying brain plasticity in transgenic mice.

Photothrombotic Ischemia: A Minimally Invasive and Reproducible Photochemical Cortical Lesion Model for Mouse Stroke Studies

The lack of mechanistic understanding of spinal cord ischemia-reperfusion injury has hindered further adjuncts to prevent paraplegia following high risk aortic operations. Thus, the development of animal models is imperative. This manuscript demonstrates reproducible lower extremity paralysis following thoracic aortic occlusion in a murine model.

Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion

Spinal cord injury is a traumatic condition that causes severe morbidity and high mortality. In this work we describe in detail a contusion model of spinal cord injury in mice followed by a transplantation of neural stem cells.

Neural Stem Cell Transplantation in Experimental Contusive Model of Spinal Cord Injury

We introduce a tissue displacement-based contusive spinal cord injury model that can produce a consistent contusive spinal cord injury in adult mice.

A Tissue Displacement-based Contusive Spinal Cord Injury Model in Mice

This protocol describes how to create a precise laminectomy for induction of stable transection-type spinal cord injury in the mouse model, with minimal collateral damage for spinal cord injury research.

Induction of Complete Transection-Type Spinal Cord Injury in Mice

Described here is the photothrombotic stroke model, where a stroke is produced through the intact skull by inducing permanent microvascular occlusion using laser illumination after administration of a photosensitive dye.

Modeling Stroke in Mice: Focal Cortical Lesions by Photothrombosis

Minimally invasive techniques and a simple laboratory device improve the reproducibility of the spinal cord injury model by reducing operative damage to the experimental animals and allowing anatomical morphology maintenance. The method is worthwhile because the reliable results and reproducible procedure facilitate investigations of the mechanisms of disease reparation.

Establishing a Mouse Contusion Spinal Cord Injury Model Based on a Minimally Invasive Technique

The present protocol simulating central cord syndrome (CCS) in mice has improved repeatability and minimized operation damage to the experimental animals, avoiding disrupting the anatomical structure excessively. The strategy in this study is advantageous because it allows for research into injury mechanisms by producing consistent results.

Establishment of Central Cord Syndrome Model in C57BL/6J Mouse

Using an all-optical approach, ischemic stroke is induced while simultaneously recording neuronal Ca2+ activity using a fluorescent biosensor in the emerging stroke core of an awake, behaving mouse.

Simultaneous Photothrombosis and Fiber Photometry to Induce and Monitor Ischemic Stroke in Behaving Mice

Learn photothrombosis-induced focal ischemia to model spinal cord injury in mice. This reproducible method uses surgical exposure, dye administration, and vessel irradiation to study injury mechanisms and test neuroprotective therapies.

Photothrombosis-induced Focal Ischemia as a Model of Spinal Cord Injury in Mice

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