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Spontaneously Hypertensive Rat
Spontaneously hypertensive rat (SHR) is a laboratory rat which is an animal model of primary hypertension, used to study cardiovascular disease. It is the most studied model of hypertension measured as number of publications. The SHR strain was obtained during the 1960s by Okamoto and colleagues, who started breeding Wistar-Kyoto rats with high blood pressure. Pathophysiology Hypertensive development begins around 5–6 weeks of age, reaching systolic pressures between 180 and 200 mmHg in the adult age phase. Starting between 40 and 50 weeks, SHR develops characteristics of cardiovascular disease, such as vascular and cardiac hypertrophy. Blood pressure in SHR depends on the kidney Hypertensive development is somehow connected to the kidney. Transplanting a kidney from SHR to a normotensive Wistar rat increases blood pressure in the recipient. Conversely, transferring a Wistar kidney to SHR normalizes blood pressure in the recipient. This also happens if transplantation take ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laboratory Rat
Laboratory rats or lab rats are strain (biology), strains of the rat subspecies ''Rattus norvegicus domestica'' (Domestic Norwegian rat) which are bred and kept for scientific research. While Animal testing on rodents, less commonly used for research than laboratory mice, rats have served as an important animal model for research in psychology and biomedical science, and "lab rat" is commonly used as an idiom for a test subject. Origins of rat breeding In 18th-century Europe, wild brown rats (''Rattus norvegicus'') ran rampant and this infestation fueled the industry of rat-catching. Rat-catchers would not only make money by trapping the rodents, but also by selling them rat meat, for food or, more commonly, for rat-baiting. Rat-baiting was a popular sport, which involved filling a pit with rats and timing how long it took for a terrier to kill them all. Over time, breeding the rats for these contests may have produced color variations, notably the albino rat, albino and hoode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terje Sagvolden
Terje Sagvolden (12 February 1945 – 12 January 2011, Oslo) was a Norwegian behavioral neuroscientist, a professor at the Universities of Oslo and Tromsø, and adjunct professor at the University of Maryland, Baltimore County. Research Sagvolden's research career started with his work for his PhD, which he obtained in 1979 from the University of Oslo based on a thesis entitled ''Behavioral Changes in Rats with Septal Lesions: Effects of Water-Deprivation Level and Intensity of Electrical Shocks''. Sagvolden is best known for the discovery that the SHR rat strain is hyperactive. Over the next decades, he then went on to demonstrate that this strain is a valid animal model for attention deficit hyperactivity disorder (ADHD). Subsequently, Sagvolden also showed that the WKY/NCrl rat strain showed inattention, but no impulsivity or hyperactivity, and validated this strain as an animal model of inattentive ADHD. Over the course of his career, Sagvolden worked not only with rats, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annual Reviews (publisher)
Annual Reviews is an independent, non-profit academic publishing company based in San Mateo, California. As of 2021, it publishes 51 journals of review articles and ''Knowable Magazine'', covering the fields of List of life sciences, life, Biomedical sciences, biomedical, Outline of physical science, physical, and Social science, social sciences. Review articles are usually "peer-invited" solicited submissions, often planned one to two years in advance, which go through a peer-review process. The organizational structure has three levels: a volunteer board of directors, editorial committees of experts for each journal, and paid employees. Annual Reviews' stated Mission statement, mission is to synthesize and integrate knowledge "for the progress of science and the benefit of society". The first Annual Reviews journal, the ''Annual Review of Biochemistry'', was published in 1932 under the editorship of Stanford University chemist J. Murray Luck, who wanted to create a resource ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Proliferation
Cell proliferation is the process by which ''a cell grows and divides to produce two daughter cells''. Cell proliferation leads to an exponential increase in cell number and is therefore a rapid mechanism of tissue growth. Cell proliferation requires both cell growth and cell division to occur at the same time, such that the average size of cells remains constant in the population. Cell division can occur without cell growth, producing many progressively smaller cells (as in cleavage of the zygote), while cell growth can occur without cell division to produce a single larger cell (as in growth of neurons). Thus, cell proliferation is not synonymous with either cell growth or cell division, despite these terms sometimes being used interchangeably. Stem cells undergo cell proliferation to produce proliferating "transit amplifying" daughter cells that later differentiate to construct tissues during normal development and tissue growth, during tissue regeneration after da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Migration
Cell migration is a central process in the development and maintenance of multicellular organisms. Tissue formation during embryogenesis, embryonic development, wound healing and immune system, immune responses all require the orchestrated movement of cells in particular directions to specific locations. Cells often migrate in response to specific external signals, including chemotaxis, chemical signals and mechanotaxis, mechanical signals. Errors during this process have serious consequences, including intellectual disability, cardiovascular disease, vascular disease, tumor, tumor formation and metastasis. An understanding of the mechanism by which cells migrate may lead to the development of novel therapeutic strategies for controlling, for example, invasive tumour cells. Due to the highly viscous environment (low Reynolds number), cells need to continuously produce forces in order to move. Cells achieve active movement by very different mechanisms. Many less complex prokaryotic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocyte
Monocytes are a type of leukocyte or white blood cell. They are the largest type of leukocyte in blood and can differentiate into macrophages and monocyte-derived dendritic cells. As a part of the vertebrate innate immune system monocytes also influence adaptive immune responses and exert tissue repair functions. There are at least three subclasses of monocytes in human blood based on their phenotypic receptors. Structure Monocytes are amoeboid in appearance, and have nongranulated cytoplasm. Thus they are classified as agranulocytes, although they might occasionally display some azurophil granules and/or vacuoles. With a diameter of 15–22 μm, monocytes are the largest cell type in peripheral blood. Monocytes are mononuclear cells and the ellipsoidal nucleus is often lobulated/indented, causing a bean-shaped or kidney-shaped appearance. Monocytes compose 2% to 10% of all leukocytes in the human body. Development Monocytes are produced by the bone marrow from prec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Cell
A blood cell (also called a hematopoietic cell, hemocyte, or hematocyte) is a cell produced through hematopoiesis and found mainly in the blood. Major types of blood cells include red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). Together, these three kinds of blood cells add up to a total 45% of the blood tissue by volume, with the remaining 55% of the volume composed of plasma, the liquid component of blood. Red blood cells Red blood cells or ''erythrocytes'' primarily carry oxygen and collect carbon dioxide through the use of hemoglobin. Hemoglobin is an iron-containing protein that gives red blood cells their color and facilitates transportation of oxygen from the lungs to tissues and carbon dioxide from tissues to the lungs to be exhaled. Red blood cells are the most abundant cell in the blood, accounting for about 40–45% of its volume. Red blood cells are circular, biconcave, disk-shaped and deformable to allow them to sque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smooth Muscle Cell
Smooth muscle is one of the three major types of vertebrate muscle tissue, the others being skeletal and cardiac muscle. It can also be found in invertebrates and is controlled by the autonomic nervous system. It is non- striated, so-called because it has no sarcomeres and therefore no striations (''bands'' or ''stripes''). It can be divided into two subgroups, ''single-unit'' and ''multi-unit'' smooth muscle. Within single-unit muscle, the whole bundle or sheet of smooth muscle cells contracts as a syncytium. Smooth muscle is found in the walls of hollow organs, including the stomach, intestines, bladder and uterus. In the walls of blood vessels, and lymph vessels, (excluding blood and lymph capillaries) it is known as vascular smooth muscle. There is smooth muscle in the tracts of the respiratory, urinary, and reproductive systems. In the eyes, the ciliary muscles, iris dilator muscle, and iris sphincter muscle are types of smooth muscles. The iris dilator and sphincter muscles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vascular Permeability
Vascular permeability, often in the form of capillary permeability or microvascular permeability, characterizes the permeability of a blood vessel wall–in other words, the blood vessel wall's capacity to allow for the flow of small molecules (such as drugs, nutrients, water, or ions) or even whole cells (such as lymphocytes on their way to a site of inflammation) in and out of the vessel. Blood vessel walls are lined by a single layer of endothelial cells. The gaps between endothelial cells (cell junctions) are strictly regulated depending on the type and physiological state of the tissue. There are several techniques to measure vascular permeability to certain molecules. For instance, the cannulation of a single microvessel with a micropipette: the microvessel is perfused with a certain pressure, occluded downstream, and then the velocity of some cells will be related to the permeability.Michel, C. C., Mason, J. C., Curry, F. E. & Tooke, J. E. Development of Landis Techn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypertrophy
Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It is distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number. Although hypertrophy and hyperplasia are two distinct processes, they frequently occur together, such as in the case of the hormonally induced proliferation and enlargement of the cells of the uterus during pregnancy. Eccentric hypertrophy is a type of hypertrophy where the walls and chamber of a hollow organ undergo growth in which the overall size and volume are enlarged. It is applied especially to the left ventricle of heart. Sarcomeres are added in series, as for example in dilated cardiomyopathy (in contrast to hypertrophic cardiomyopathy, a type of concentric hypertrophy, where sarcomeres are added in parallel). Gallery Gould Pyle 234.jpg, Breasts Hypertrophied clitoris.jpg, Clitoris Head of a boy with hypertrophy of the ear Wellcome L0062496.j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperplasia
Hyperplasia (from ancient Greek ὑπέρ ''huper'' 'over' + πλάσις ''plasis'' 'formation'), or hypergenesis, is an enlargement of an organ or tissue caused by an increase in the amount of Tissue (biology), organic tissue that results from cell proliferation. It may lead to the Gross anatomy, gross enlargement of an organ, and the term is sometimes confused with benign neoplasia or benign tumor. Hyperplasia is a common preneoplastic response to stimulus. Microscopically, cells resemble normal cells but are increased in numbers. Sometimes cells may also be increased in size (hypertrophy). Hyperplasia is different from hypertrophy in that the Cellular adaptation, adaptive cell change in hypertrophy is an increase in the cell size, ''size'' of cells, whereas hyperplasia involves an increase in the ''number'' of cells. Causes Hyperplasia may be due to any number of causes, including proliferation of basal layer of epidermis to compensate skin loss, Chronic inflammation, chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arterial Wall
An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in the pulmonary circulation that carry blood to the lungs for oxygenation, and the umbilical arteries in the fetal circulation that carry deoxygenated blood to the placenta. It consists of a multi-layered artery wall wrapped into a tube-shaped channel. Arteries contrast with veins, which carry deoxygenated blood back towards the heart; or in the pulmonary and fetal circulations carry oxygenated blood to the lungs and fetus respectively. Structure The anatomy of arteries can be separated into gross anatomy, at the macroscopic level, and microanatomy, which must be studied with a microscope. The arterial system of the human body is divided into systemic arteries, carrying blood from the heart to the whole body, and pulmonary arteries, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
