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Langendorff Heart
The Langendorff heart or isolated perfused heart assay is an ''ex vivo'' technique used in pharmacological and physiological research using animals and also humans. It allows the examination of cardiac contractile strength and heart rate without the complications of an intact animal or human. After 90 years this method is still being used. Method In the Langendorff preparation, the heart is removed from the animal's or human's body, severing the blood vessels; it is then perfused in a reverse fashion ( retrograde perfusion) via the aorta, usually with a nutrient rich, oxygenated solution (e.g. Krebs–Henseleit solution or Tyrode's solution). The backwards pressure causes the aortic valve to shut, forcing the solution into the coronary vessels, which normally supply the heart tissue with blood. This feeds nutrients and oxygen to the cardiac muscle, allowing it to continue beating for several hours after its removal from the animal or human. This is a useful preparation becau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ischemic Preconditioning Of The Heart
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue i.e. hypoxia and microvascular dysfunction. It also implies local hypoxia in a part of a body resulting from constriction (such as vasoconstriction, thrombosis, or embolism). Ischemia causes not only insufficiency of oxygen, but also reduced availability of nutrients and inadequate removal of metabolic wastes. Ischemia can be partial (poor perfusion) or total blockage. The inadequate delivery of oxygenated blood to the organs must be resolved either by treating the cause of the inadequate delivery or reducing the oxygen demand of the system that needs it. For example, patients with myocardial ischemia have a decreased blood flow to the heart and are prescribed with medicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krebs–Henseleit Solution
Krebs–Henseleit solution, developed by Hans Krebs and Kurt Henseleit, is a solution containing sodium (Na), potassium (K), chloride (Cl), calcium (Ca), magnesium sulfate (MgSO4), bicarbonate (HCO3), phosphate (PO4), glucose, and sometimes supplemented with albumin, and tromethamine (THAM). It has been used experimentally, for instance to study arteries ''ex vivo'', in Langendorff heart preparations, and during isolated muscle testing of mammalian skeletal muscles Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle .... References Solutions {{pharma-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retrograde Perfusion
Retrograde perfusion (retroperfusion) is an artificial method of providing blood supply to an organ by delivering oxygenated blood through the veins. It may be performed during surgery that interrupts the normal arterial supply of blood to that organ. For instance, when performing surgery that interrupts the cerebral arteries, a hose placed into the femoral artery and the superior vena cava can redirect blood up the internal jugular vein to supply the brain. This technique was pioneered by Oscar Langendorff, who perfused mamallian hearts ex vivo for research applications. Thus, it is often called Langendorff perfusion.Bell, R., Mocanu, M. & Yellon, D. Retrograde heart perfusion: The Langendorff technique of isolated heart perfusion. Journal of Molecular and Cellular Cardiology 50, 940-950 (2011). See also * Langendorff heart * Perfusion Perfusion is the passage of fluid through the circulatory system or lymphatic system to an organ or a tissue, usually referring to the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oskar Langendorff
Oskar Langendorff (1 February 1853 in Breslau – 10 May 1908 in Rostock; his first name is sometimes given as "Oscar") was a German physician and physiologist known primarily for his experiments on the isolated perfused heart, the so-called Langendorff Heart apparatus. In addition, he is credited with discoveries in respiration and in the conduction of impulses in the sympathetic and peripheral nervous system. His work has served as the basis for the use of retrograde perfusion in science and medicine. Scientific career After studying medicine in Wrocław (Breslau), Berlin and Freiburg im Breisgau Langendorff obtained his Ph.D. at the University of Königsberg in 1875, subsequently working there as a research assistant. He received his habilitation in 1879 with the physiologist Ludimar Hermann and after 1884 held a post as associate professor. In 1886, he was elected to membership in the German Academy of Sciences Leopoldina. From 1892 till his death in 1908 Langendorff was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oscar Langendorff
Oskar Langendorff (1 February 1853 in Breslau – 10 May 1908 in Rostock; his first name is sometimes given as "Oscar") was a German physician and physiologist known primarily for his experiments on the isolated perfused heart, the so-called Langendorff Heart apparatus. In addition, he is credited with discoveries in respiration and in the conduction of impulses in the sympathetic and peripheral nervous system. His work has served as the basis for the use of retrograde perfusion in science and medicine. Scientific career After studying medicine in Wrocław (Breslau), Berlin and Freiburg im Breisgau Langendorff obtained his Ph.D. at the University of Königsberg in 1875, subsequently working there as a research assistant. He received his habilitation in 1879 with the physiologist Ludimar Hermann and after 1884 held a post as associate professor. In 1886, he was elected to membership in the German Academy of Sciences Leopoldina. From 1892 till his death in 1908 Langendorff was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagenase
Collagenases are enzymes that break the peptide bonds in collagen. They assist in destroying extracellular structures in the pathogenesis of bacteria such as ''Clostridium''. They are considered a virulence factor, facilitating the spread of gas gangrene. They normally target the connective tissue in muscle cells and other body organs. Collagen, a key component of the animal extracellular matrix, is made through cleavage of pro-collagen by collagenase once it has been secreted from the cell. This stops large structures from forming inside the cell itself. In addition to being produced by some bacteria, collagenase can be made by the body as part of its normal immune response. This production is induced by cytokines, which stimulate cells such as fibroblasts and osteoblasts, and can cause indirect tissue damage. Therapeutic uses Collagenases have been approved for medical uses for: * treatment of Dupuytren's contracture and Peyronie's disease (Xiaflex). * wound healing (Sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aortic Valve
The aortic valve is a valve in the heart of humans and most other animals, located between the left ventricle and the aorta. It is one of the four valves of the heart and one of the two semilunar valves, the other being the pulmonary valve. The aortic valve normally has three cusps or leaflets, although in 1–2% of the population it is found to congenitally have two leaflets. The aortic valve is the last structure in the heart the blood travels through before stopping the flow through the systemic circulation. Structure The aortic valve normally has three cusps however there is some discrepancy in their naming. They may be called the left coronary, right coronary and non-coronary cusp. Some sources also advocate they be named as a left, right and posterior cusp. Anatomists have traditionally named them the left posterior (origin of left coronary), anterior (origin of the right coronary) and right posterior. The three cusps, when the valve is closed, contain a sinus called an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrode's Solution
Tyrode's solution is a solution that is roughly isotonic with interstitial fluid and used in physiological experiments and tissue culture. It resembles lactated Ringer's solution, but contains magnesium, a sugar (usually glucose) as an energy source and uses bicarbonate and phosphate as a buffer instead of lactate. Some variations also include phosphate and sulfate ions. It must be gassed with 95% oxygen and N2, 5% carbon dioxide when used for cell culture applications and physiology experiments in order to achieve an appropriate pH. With the addition of extra potassium salt, it can be used to prepare a cardioplegic solution. Development Tyrode's solution was invented by Maurice Vejux Tyrode (1878–1930), an American pharmacologist. The solution was a modification of Ringer-Locke's solution. Therapy Tyrode's solution is often used for irrigation of the peritoneum. It was also recommended by at least one physician as a dietary supplement, because of its inorganic sal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aorta
The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes oxygenated blood to all parts of the body through the systemic circulation. Structure Sections In anatomical sources, the aorta is usually divided into sections. One way of classifying a part of the aorta is by anatomical compartment, where the thoracic aorta (or thoracic portion of the aorta) runs from the heart to the diaphragm. The aorta then continues downward as the abdominal aorta (or abdominal portion of the aorta) from the diaphragm to the aortic bifurcation. Another system divides the aorta with respect to its course and the direction of blood flow. In this system, the aorta starts as the ascending aorta, travels superiorly from the heart, and then makes a hairpin turn known as the aortic arch. Following the aortic arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ex Vivo
''Ex vivo'' (Latin: "out of the living") literally means that which takes place outside an organism. In science, ''ex vivo'' refers to experimentation or measurements done in or on tissue from an organism in an external environment with minimal alteration of natural conditions. Testing the effect of compounds on skin biopsies is an example of ''ex vivo'' research, while isolating the primary cells from that biopsy and creating a 3D cell culture model is an example of ''in vitro'' research. Both use human tissues, but the former is a more complex and translational environment for drug testing. A primary advantage of using ''ex vivo'' tissues is the ability to perform tests or measurements that would otherwise not be possible or ethical in living subjects. Tissues may be experimented on in many ways, including in part (e.g. cardiac contractility models using atrial pectinate muscles) or as whole organs (e.g. isolated perfused heart model). Examples of ''ex vivo'' models include: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retrograde Perfusion
Retrograde perfusion (retroperfusion) is an artificial method of providing blood supply to an organ by delivering oxygenated blood through the veins. It may be performed during surgery that interrupts the normal arterial supply of blood to that organ. For instance, when performing surgery that interrupts the cerebral arteries, a hose placed into the femoral artery and the superior vena cava can redirect blood up the internal jugular vein to supply the brain. This technique was pioneered by Oscar Langendorff, who perfused mamallian hearts ex vivo for research applications. Thus, it is often called Langendorff perfusion.Bell, R., Mocanu, M. & Yellon, D. Retrograde heart perfusion: The Langendorff technique of isolated heart perfusion. Journal of Molecular and Cellular Cardiology 50, 940-950 (2011). See also * Langendorff heart * Perfusion Perfusion is the passage of fluid through the circulatory system or lymphatic system to an organ or a tissue, usually referring to the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfusion
Perfusion is the passage of fluid through the circulatory system or lymphatic system to an organ or a tissue, usually referring to the delivery of blood to a capillary bed in tissue. Perfusion is measured as the rate at which blood is delivered to tissue, or volume of blood per unit time (blood flow) per unit tissue mass. The SI unit is m3/(s·kg), although for human organs perfusion is typically reported in ml/min/g. The word is derived from the French verb "perfuser" meaning to "pour over or through". All animal tissues require an adequate blood supply for health and life. Poor perfusion (malperfusion), that is, ischemia, causes health problems, as seen in cardiovascular disease, including coronary artery disease, cerebrovascular disease, peripheral artery disease, and many other conditions. Tests verifying that adequate perfusion exists are a part of a patient's assessment process that are performed by medical or emergency personnel. The most common methods include evalua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
