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Blood Pressure: Pressure of the Blood on the Arteries and other Blood vessels.

Blood Pressure Measurement

JoVE 10083

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA


The term blood pressure (BP) describes lateral pressures produced by blood upon the vessel walls. BP is a vital sign obtained routinely in hospital and outpatient settings, and is one of the most common medical assessments performed around…

 Physical Examinations I

Noninvasive Blood Pressure Measurement Techniques

JoVE 10478

Source: Hamna J. Qureshi and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana



Here we will highlight the key similarities and differences of noninvasive blood pressure measurement techniques between humans and rodents and examine the engineering principles…

 Biomedical Engineering

Physiology of the Circulatory System- Concept

JoVE 10625

Homeostasis

Conditions in the external environment of an organism can change rapidly and drastically. To survive, organisms must maintain a fairly constant internal environment, which involves continuous regulation of temperature, pH, and other factors. This balanced state is known as homeostasis, which describes the processes by which organisms maintain their optimal internal…

 Lab Bio

Blood Withdrawal I

JoVE 10246

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN


Blood collection is a common requirement for research studies that involve mice and rats. The method of blood withdrawal in mice and rats is dependent upon the volume of blood needed, the frequency of the sampling, the health status of the …

 Lab Animal Research

Physiology of the Circulatory System - Student Protocol

JoVE 10570

Measuring Circulatory System Function in Humans
Before starting the experiment go to the front of the room and collect an alcohol swab, a sphygmomanometer, and a stethoscope.
Clean the earpieces with the alcohol swab and then insert them into your ears.
To check if the stethoscope is in the on position, gently tap the flat metal disc called…

 Lab Bio

Arterial Line Placement

JoVE 10178

Source: Sharon Bord, MD, Department of Emergency Medicine, The Johns Hopkins University School of Medicine, Maryland, USA


When monitoring patients, it is important to obtain values that are accurate and reliable. Blood pressure monitoring is one of the essential vital signs, and for a majority of patients, measuring it utilizing…

 Emergency Medicine and Critical Care

Hormonal Regulation

JoVE 10893

The renin-aldosterone system is an endocrine system which guides the renal absorption of water and electrolytes, thus managing blood pressure and osmoregulation. Activation of the system begins in the kidneys with a small cluster of cells adjacent to the afferent and efferent blood vessels of the renal corpuscle. As the nephrons are filtering blood, juxtaglomerular cells monitor blood pressure. If they detect a decrease in pressure, they release the hormone renin into the bloodstream. Circulating renin interacts with angiotensinogen, a precursor protein synthesized by the liver, to create angiotensin I. A final step cleaves angiotensin I into angiotensin II, a process achieved by angiotensin-converting enzyme, or ACE, which is released by the lungs. Angiotensin II temporarily increases blood pressure by contracting smaller blood vessels. It also induces the release of aldosterone from the adrenal cortex of the kidneys. Aldosterone directly stimulates the reabsorption of sodium and the excretion of potassium by the kidneys to maintain electrolyte balance. Moreover, circulating levels of aldosterone stimulate the release of antidiuretic hormone, or ADH, by the hypothalamus in the brain. Upon reaching the kidneys, ADH upregulates aquaporin channels in the nephrons which increase the water retention in the blood vessels. The combined effects of

 Core: Regulation and Excretion

Paracrine Signaling

JoVE 10716

Paracrine signaling allows cells to communicate with their immediate neighbors via secretion of signaling molecules. The signal only triggers a response in nearby target cells as the signal molecules degrade quickly or are inactivated by nearby cells if not taken up. Prominent examples of paracrine signaling include nitric oxide signaling in blood vessels, synaptic signaling of neurons, the blood clotting system, tissue repair/wound healing, and local allergic skin reactions. One of the essential paracrine signaling molecules is the gas nitric oxide (NO). Nitric oxide is produced by a family of enzymes known as nitric oxide synthases. Blood vessels contain several layers of cells. The innermost layer of cells is the endothelium. Endothelial cells have nitric oxide synthase, which produces nitric oxide that diffuses in all directions. The nitric oxide that reaches the blood does not contribute to signaling but immediately reacts with biochemicals, such as hemoglobin. Nitric oxide molecules that diffuse in the opposite direction, towards the next layer of the blood vessel, participate in some important signaling. The layer just exterior to the endothelium is made up of smooth muscle cells. The function of smooth muscle cells is to contract. When these cells contract, they clamp down on the blood vessel, narrowing its diameter and consequently rais

 Core: Cell Signaling

Filtration

JoVE 10891

The function of the kidneys is to filter, reabsorb, secrete, and excrete. Every day the kidneys filter nearly 180 liters of blood, initially removing water and solutes but ultimately returning nearly all filtrates into circulation with the help of osmoregulatory hormones. This process removes wastes and toxins but is also crucial to maintain water and electrolyte levels. Most of these functions are performed by the tiny but numerous nephrons contained within the kidneys. Blood enters the renal corpuscle of the nephron through a glomerulus of capillaries. The capillaries are surrounded by a structure called the Bowman’s capsule which absorbs water and most solutes from the blood. The blood pressure from capillaries pushes these into the capsules. If the blood pressure is too high, as seen in hypertension, the capillaries can weaken and harden, reducing the ability of the kidney to filter the blood. The filtrate from the corpuscles empty into the proximal convoluted tubules and the descending portions of the Loop of Henle. Here nearly 70% of solutes—salt, glucose, amino acids, and bicarbonates—are reabsorbed into the surrounding capillaries. Circulating blood hormones involved in osmoregulation induce reabsorption of sodium, calcium, or more water if needed to increase or decrease blood pressure and regulate electrolytes. Sec

 Core: Regulation and Excretion

Peripheral Vascular Exam Using a Continuous Wave Doppler

JoVE 10123

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT


Peripheral vascular disease (PVD) is a common condition affecting older adults and includes disease of the peripheral arteries and veins. While the history and physical exam offer clues to its diagnosis, Doppler ultrasound has become a…

 Physical Examinations I

Physiology of the Circulatory System - Prep Student

JoVE 10569

Measuring Blood Pressure
To prepare for the blood pressure exercise, simply place the appropriate number of alcohol swabs, sphygmomanometers, and stethoscopes at the front of the classroom.
Be sure to check over each of the component parts of the sphygmomanometers, including the tubing, cuff, manometer, and bulb to ensure they are undamaged.…

 Lab Bio

Measuring Vital Signs

JoVE 10107

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA


The vital signs are objective measurements of a patient's clinical status. There are five commonly accepted vital signs: blood pressure, heart rate, temperature, respiratory rate, and oxygen saturation. In many practices, pain is…

 Physical Examinations I

Polygenic Traits

JoVE 10778

When more than one gene is responsible for a given phenotype, the trait is considered polygenic. Human height is a polygenic trait. Studies have uncovered hundreds of loci that influence height, and there are believed to be many more. Due to the high number of genes involved, as well as environmental and nutritional factors, height varies significantly within a given population. The distribution of height forms a bell-shaped curve, with relatively few individuals in the population at the minimum or maximum heights and the majority of the population in the middle height range. Most polygenic traits, like weight, blood pressure, and aspects of fingerprint patterns, also plot as bell-shaped curves. Although Mendel’s seminal work on genetic inheritance focused on traits that arose from single genes, experiments such as genome-wide association studies have revealed that many human traits develop through the cooperation of multiple gene products. The collaboration of numerous genes to influence a phenotype constitutes a polygenic (i.e., “many gene”) trait. One example of a polygenic trait is human height. Hundreds of loci are implicated in human height variability, and it is believed that there are more that have not yet been identified. Many of these genes directly or indirectly affect cartilage in growth plates, which are found in

 Core: Classical and Modern Genetics

Needle Thoracostomy

JoVE 10233

Source: Rachel Liu, BAO, MBBCh, Emergency Medicine, Yale School of Medicine, New Haven, Connecticut, USA


A tension pneumothorax is a life-threatening situation in which excess air is introduced into the pleural space surrounding the lung, either through trauma to the chest cavity or as a spontaneous leak of air from the lung itself. Air…

 Emergency Medicine and Critical Care

Kidney Structure

JoVE 10890

The kidneys are two large bean-shaped organs located in the upper abdomen. They filter the blood several times a day to remove toxins and rebalance water and electrolytes of the circulatory system via the renal veins. The kidneys receive blood directly from the heart via the renal arteries. These arteries enter the kidney at the hilum, the concave surface of the bean, where they branch and divide into smaller vessels and capillaries. The renal cortex is the thick outer layer of the kidney. It houses renal corpuscles, where capillaries come into close contact with the end of a renal tubule. The end of the tubule, or Bowman’s capsule, surrounds a net of capillaries that looks like a ball, the glomerulus. This unusual arrangement of the capillaries increases the surface area where the end of the renal tubule and the capillaries interact. From the Bowman’s capsule, the convoluted tubules extend into the Loop of Henle that lay in the renal medulla, the tissue beneath the renal cortex. Cortical intrusions structure the medulla into multiple renal pyramids. The apex of each pyramid points towards the hilum area, thus draining the collecting ducts into calyces in the renal pelvis. As the pelvis fills, urine is emptied into the ureter. The ureter connects the kidneys to the bladder, where urine is stored before being eliminated. The renal corp

 Core: Regulation and Excretion

Pericardiocentesis

JoVE 10236

Source: Rachel Liu, BAO, MBBCh, Emergency Medicine, Yale School of Medicine, New Haven, Connecticut, USA


The heart lies within the pericardium, a relatively inelastic fibrous sac. The pericardium has some compliance to stretch when fluid is slowly introduced into the pericardial space. However, rapid accumulation overwhelms pericardial…

 Emergency Medicine and Critical Care

Allergic Reactions

JoVE 10901

We speak of an allergy when the immune system triggers a response against a benign foreign structure, like food, pollen or pet dander. These elicitors are called allergens. If the immune system of a hypersensitive individual was primed against a specific allergen, it will trigger allergic symptoms during every subsequent encounter of the allergen. Symptoms can be mild, such as hay fever, to severe, such as potentially fatal anaphylactic shock. The immune system is crucial for defending an organism against bacteria, viruses, fungi, toxins, and parasites. However, in a hypersensitive response, it can be triggered by harmless substances and cause unpleasant or potentially life-threatening overreactions, called allergies. The first step toward establishing an allergy is sensitization. For instance, an individual becomes allergic to the pollen of ragweed when, for the first time, immune cells in the respiratory passage take up the pollen and degrade the allergens into fragments. These immune cells are called antigen-presenting cells, or APCs, because they display the degraded allergen fragments on their surface. Examples of APCs are dendritic cells, macrophages and B cells. Subsequently, APCs activate encountered Type 2 helper T cells (Th2). The activated Th2 then release chemical signals (e.g., cytokines) that cause B cells to differen

 Core: Immune System

Rodent Handling and Restraint Techniques

JoVE 10221

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN 


It has been demonstrated that even minimal handling of mice and rats is stressful to the animals. Handling for cage changing and other noninvasive procedures causes an increase in heart rate, blood pressure, and other physiological…

 Lab Animal Research

Cardiac Exam III: Abnormal Heart Sounds

JoVE 10135

Source: Suneel Dhand, MD, Attending Physician, Internal Medicine, Beth Israel Deaconess Medical Center


Having a fundamental understanding of normal heart sounds is the first step toward distinguishing the normal from the abnormal. Murmurs are sounds that represent turbulent and abnormal blood flow across a heart valve. They are caused…

 Physical Examinations I

Peripheral Vascular Exam

JoVE 10122

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT


The prevalence of peripheral vascular disease (PVD) increases with age and is a significant cause of morbidity in older patients, and peripheral artery disease (PAD) is associated with cardiovascular and cerebrovascular complications.…

 Physical Examinations I

What Are Osmoregulation and Excretion?

JoVE 11001

Organisms must keep bodily fluids at a constant temperature and pH while maintaining specific solute concentrations in order to support life functions. Osmoregulation is the process that balances solute and water levels.

Osmosis is the tendency of water to move from solutions with lower ion concentrations, or osmolarities, to those with higher ion concentrations. Osmosis occurs in response to differences in the molecular concentrations of solutions separated by a semipermeable membrane. Bodily fluids, which are separated by such membranes, contain water, non-electrolytes, and electrolytes—solutes that dissolve into ions in water. Both electrolytes and non-electrolytes influence osmotic balance. However, since the more important factor to osmosis is solute number, rather than size, the contribution of electrolytes is more significant. Unlike water, electrolytes cannot diffuse passively through membranes but rely on facilitated diffusion and active transport. In facilitated diffusion, protein-based channels move solutes across membranes. Conversely, energy is used to move ions against concentration gradients in active transport. When animals ingest food, material that cannot be used is excreted from the body. Excretory systems in nature involve tradeoffs between conserving energy and water. Nitrogen is among the most significant

 Core: Regulation and Excretion

Anesthesia Induction and Maintenance

JoVE 10263

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN


The Guide for the Care and Use of Laboratory Animals ("The Guide") states that pain assessment and alleviation are integral components of the veterinary care of laboratory animals.1 The definition of anesthesia is the loss …

 Lab Animal Research

RC/RL/LC Circuits

JoVE 10318

Source: Yong P. Chen, PhD, Department of Physics & Astronomy, College of Science, Purdue University, West Lafayette, IN


Capacitors (C), inductors (L), and resistors (R) are each an important circuit element with distinct behaviors. A resistor dissipates energy and obeys Ohm's law, with its voltage proportional to its current. A…

 Physics II

Modeling Social Stress

JoVE 5429

Stress negatively affects our quality of life. In particular, some individuals experience social stress when placed in a social environment that they are unfamiliar with or have difficulty adjusting to. Since it is hard to examine mechanisms of social stress in humans, modeling this condition in animals may help scientist in developing new therapies for treating this commonly encountered…

 Behavioral Science

Continuous Blood Sampling in Small Animal Positron Emission Tomography/Computed Tomography Enables the Measurement of the Arterial Input Function

1Institute of Anatomy, Rostock University Medical Center, 2Department of Nuclear Medicine, Rostock University Medical Center, 3Core Facility Multimodal Small Animal Imaging, Rostock University Medical Center, 4Rudolf-Zenker-Institute for Experimental Surgery, Rostock University Medical Center

JoVE 59701

 Medicine

Invasive Hemodynamic Characterization of the Portal-hypertensive Syndrome in Cirrhotic Rats

1Div. of Gastroenterology and Hepatology, Dept. of Internal Medicine III, Medical University of Vienna, Vienna, Austria, 2Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria, 3Center of Biomedical Research, Medical University of Vienna, Vienna, Austria

JoVE 57261

 Medicine

Lateral Fluid Percussion: Model of Traumatic Brain Injury in Mice

1Department of Neuroscience and Cell Biology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, 2Spinal Cord and Brain Injury Research Center, 3Department of Anatomy and Neurobiology, Department of Physical Medicine and Rehabilitation, University of Kentucky Chandler Medical Center

JoVE 3063

 Neuroscience

Isolation of Retinal Arterioles for Ex Vivo Cell Physiology Studies

1Centre for Experimental Medicine, Queen's University of Belfast, 2Centre for Biomedical Sciences (Education), Queen's University of Belfast, 3Department of Pharmaceutical Chemistry and Pharmacognosy, Naresuan University, 4School of Medicine, Dentistry and Biomedical Sciences, Queen's University of Belfast

JoVE 57944

 Biology

Preclinical Model of Hind Limb Ischemia in Diabetic Rabbits

1Department of Biomedical Engineering, University of Texas at Austin, 2Division of Cardiology, University of Texas McGovern Medical School, 3Center for Laboratory Animal Medicine and Care, UT Health Science Center at Houston, 4Memorial Herman Heart and Vascular Center, Texas Medical Center, 5Institute for Cellular and Molecular Biology, University of Texas at Austin, 6The Institute for Computational Engineering and Sciences, University of Texas at Austin, 7Institute for Biomaterials, Drug Delivery and Regenerative Medicine, University of Texas at Austin

JoVE 58964

 Medicine

Performing Permanent Distal Middle Cerebral with Common Carotid Artery Occlusion in Aged Rats to Study Cortical Ischemia with Sustained Disability

1Wolfson Centre for Age-Related Diseases, King's College London, University of London, 2Department of Neuroimaging, James Black Centre, Institute of Psychiatry, King's College London, University of London, 3Institute of Neuroscience and Psychology, Wellcome Surgical Institute, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, 4Research Service, Edward Hines Jr. VA Hospital, 5Neurology Service, Edward Hines Jr. VA Hospital, 6Department of Molecular Pharmacology and Therapeutics, Neuroscience Research Institute, Loyola University Chicago, 7Department of Oncology, The Gray Institute for Radiation, Oncology and Biology, University of Oxford

JoVE 53106

 Medicine
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