Renal cortex

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Renal cortex
Blausen 0592 KidneyAnatomy 01.png
Kidney anatomy, with renal cortex labeled at top.
Illu kidney.jpg
Details
System Urinary system
Identifiers
Latin cortex renalis
MeSH D007672
TA98 A08.1.01.015
TA2 3368
FMA 15581
Anatomical terminology

The renal cortex is the outer portion of the kidney between the renal capsule and the renal medulla. [1] In the adult, it forms a continuous smooth outer zone with a number of projections (cortical columns) that extend down between the pyramids. It contains the renal corpuscles and the renal tubules except for parts of the loop of Henle which descend into the renal medulla. It also contains blood vessels and cortical collecting ducts.

The renal cortex is the part of the kidney where ultrafiltration occurs. [2] Erythropoietin is produced in the renal cortex. [3]

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Related Research Articles

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<span class="mw-page-title-main">Kidney</span> Organ that filters blood and produces urine in humans

In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and right in the retroperitoneal space, and in adult humans are about 12 centimetres in length. They receive blood from the paired renal arteries; blood exits into the paired renal veins. Each kidney is attached to a ureter, a tube that carries excreted urine to the bladder.

<span class="mw-page-title-main">Lymph node</span> Organ of the lymphatic system

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<span class="mw-page-title-main">Nephron</span> Microscopic structural and functional unit of the kidney

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<span class="mw-page-title-main">Erythropoietin</span> Protein that stimulates red blood cell production

Erythropoietin, also known as erythropoetin, haematopoietin, or haemopoietin, is a glycoprotein cytokine secreted mainly by the kidneys in response to cellular hypoxia; it stimulates red blood cell production (erythropoiesis) in the bone marrow. Low levels of EPO are constantly secreted in sufficient quantities to compensate for normal red blood cell turnover. Common causes of cellular hypoxia resulting in elevated levels of EPO include any anemia, and hypoxemia due to chronic lung disease.

<span class="mw-page-title-main">Renin–angiotensin system</span> Hormone system

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<span class="mw-page-title-main">Collecting duct system</span> Kidney system

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<span class="mw-page-title-main">Proximal tubule</span> Segment of nephron in kidneys

The proximal tubule is the segment of the nephron in kidneys which begins from the renal pole of the Bowman's capsule to the beginning of loop of Henle. At this location, the glomerular parietal epithelial cells (PECs) lining bowman’s capsule abruptly transition to proximal tubule epithelial cells (PTECs). The proximal tubule can be further classified into the proximal convoluted tubule (PCT) and the proximal straight tubule (PST).

<span class="mw-page-title-main">Renal medulla</span> Innermost part of the kidney

The renal medulla is the innermost part of the kidney. The renal medulla is split up into a number of sections, known as the renal pyramids. Blood enters into the kidney via the renal artery, which then splits up to form the segmental arteries which then branch to form interlobar arteries. The interlobar arteries each in turn branch into arcuate arteries, which in turn branch to form interlobular arteries, and these finally reach the glomeruli. At the glomerulus the blood reaches a highly disfavourable pressure gradient and a large exchange surface area, which forces the serum portion of the blood out of the vessel and into the renal tubules. Flow continues through the renal tubules, including the proximal tubule, the loop of Henle, through the distal tubule and finally leaves the kidney by means of the collecting duct, leading to the renal pelvis, the dilated portion of the ureter.

<span class="mw-page-title-main">Glomerulus (kidney)</span> Functional unit of nephron

The glomerulus is a network of small blood vessels (capillaries) known as a tuft, located at the beginning of a nephron in the kidney. Each of the two kidneys contains about one million nephrons. The tuft is structurally supported by the mesangium, composed of intraglomerular mesangial cells. The blood is filtered across the capillary walls of this tuft through the glomerular filtration barrier, which yields its filtrate of water and soluble substances to a cup-like sac known as Bowman's capsule. The filtrate then enters the renal tubule of the nephron.

<span class="mw-page-title-main">Macula densa</span> A region of juxtaglomerular apparatus in nephron of kidney

In the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the distal tubule where it touches the glomerulus. Specifically, the macula densa is found in the terminal portion of the distal straight tubule, after which the distal convoluted tubule begins.

<span class="mw-page-title-main">Cortex (anatomy)</span> Outermost layer of an organ

In anatomy and zoology, the cortex is the outermost layer of an organ. Organs with well-defined cortical layers include kidneys, adrenal glands, ovaries, the thymus, and portions of the brain, including the cerebral cortex, the best-known of all cortices.

<span class="mw-page-title-main">Vasa recta (kidney)</span> Anatomical structure of the kidney

The vasa recta of the kidney, are the straight arterioles, and the straight venules of the kidney, – a series of blood vessels in the blood supply of the kidney that enter the medulla as the straight arterioles, and leave the medulla to ascend to the cortex as the straight venules.. They lie parallel to the loop of Henle.

<span class="mw-page-title-main">Efferent arteriole</span> Blood vessel carrying blood out away from glomerulus

The efferent arterioles are blood vessels that are part of the urinary tract of organisms. Efferent means "outgoing", in this case meaning carrying blood out away from the glomerulus. The efferent arterioles form a convergence of the capillaries of the glomerulus, and carry blood away from the glomerulus that has already been filtered. They play an important role in maintaining the glomerular filtration rate despite fluctuations in blood pressure.

<span class="mw-page-title-main">Arcuate vein</span>

The arcuate vein is a vessel of the renal circulation. It is located at the border of the renal cortex and renal medulla. Arcuate veins pass around the renal pyramids at the border between the renal cortex and renal medulla in an arch shape. Arcuate veins receive blood from cortical radiate veins, and in turn deliver blood into the arcuate veins.

Sickle cell nephropathy is a type of nephropathy associated with sickle cell disease which causes kidney complications as a result of sickling of red blood cells in the small blood vessels. The hypertonic and relatively hypoxic environment of the renal medulla, coupled with the slow blood flow in the vasa recta, favors sickling of red blood cells, with resultant local infarction. Functional tubule defects in patients with sickle cell disease are likely the result of partial ischemic injury to the renal tubules.

Renal cortical necrosis (RCN) is a rare cause of acute kidney failure. The condition is "usually caused by significantly diminished arterial perfusion of the kidneys due to spasms of the feeding arteries, microvascular injury, or disseminated intravascular coagulation" and is the pathological progression of acute tubular necrosis. It is frequently associated with obstetric catastrophes such as abruptio placentae and septic shock, and is three times more common in developing nations versus industrialized nations.

The kidneys are a pair of organs of the excretory system in vertebrates, which maintains the balance of water and electrolytes in the body (osmoregulation), filters the blood, removes metabolic waste products, and in many vertebrates also produces hormones and maintains blood pressure. In healthy vertebrates, the kidneys maintain homeostasis of extracellular fluid in the body. When the blood is being filtered, the kidneys form urine, which consists of water and excess or unnecessary substances, the urine is then excreted from the body through other organs, which in vertebrates, depending on the species, may include the ureter, urinary bladder, cloaca, and urethra.

<span class="mw-page-title-main">Mammalian kidney</span> Paired organ in the urinary system of mammals

The mammalian kidneys are a pair of excretory organs of the urinary system of mammals, being functioning kidneys in postnatal-to-adult individuals. The kidneys in mammals are usually bean-shaped or externally lobulated. They are located behind the peritoneum (retroperitoneally) on the back (dorsal) wall of the body. Each kidney consists of a renal capsule, peripheral cortex, internal medulla, which can be split up into renal pyramids forming papillae with their innermost parts, calices, and renal pelvis, although the calices or renal pelvis may be absent in some species. Generally, urine produced by the cortex and medulla drains from the papillae into the calices, and then into the renal pelvis, from which urine exits the kidney through the ureter. Nitrogen-containing waste products are excreted by the kidneys in mammals mainly in the form of urea.

References

  1. Kriz, W; Bankir, L (1988). "A standard nomenclature for structures of the kidney". Kidney International. 33 (1): 1–7. doi: 10.1038/ki.1988.1 . PMID   3352156.
  2. Brenner, Barry M.; Troy, Julia L.; Daugharty, Terrance M. (1971-08-01). "The Dynamics of Glomerular Ultrafiltration in the Rat". Journal of Clinical Investigation. 50 (8): 1776–1780. doi:10.1172/JCI106667. ISSN   0021-9738. PMC   442078 . PMID   5097578.
  3. Koury, ST; Koury, MJ; Bondurant, MC; Caro, J; Graber, SE (1989-08-01). "Quantitation of erythropoietin-producing cells in kidneys of mice by in situ hybridization: correlation with hematocrit, renal erythropoietin mRNA, and serum erythropoietin concentration". Blood. 74 (2): 645–651. doi: 10.1182/blood.V74.2.645.645 . ISSN   0006-4971. PMID   2752138.