Search results
Results From The WOW.Com Content Network
Angiotensin II is the major bioactive product of the renin–angiotensin system, binding to receptors on intraglomerular mesangial cells, causing these cells to contract along with the blood vessels surrounding them; and to receptors on the zona glomerulosa cells, causing the release of aldosterone from the zona glomerulosa in the adrenal cortex.
Another system maintaining the extracellular fluid volume, peripheral resistance, and that if disturbed may lead to hypertension, is the renin–angiotensin–aldosterone system. Renin is a circulating enzyme that participates in maintaining extracellular volume and arterial vasoconstriction, therefore contributing to regulation of blood pressure.
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 (thick ascending limb of the loop of Henle), after which the distal convoluted tubule begins.
Excess secretion of renin by the juxtaglomerular cells can lead to excess activity of the renin–angiotensin system, hypertension and an increase in blood volume. This is not responsive to the usual treatment for essential hypertension , namely medications and lifestyle modification.
Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin-angiotensin-aldosterone system (RAAS)—also known as the renin-angiotensin-aldosterone axis—that increases the volume of extracellular fluid (blood plasma, lymph, and interstitial fluid) and causes arterial ...
When renal blood flow is reduced (indicating hypotension) or there is a decrease in sodium or chloride ion concentration, the macula densa of the distal tubule releases prostaglandins (mainly PGI2 and PGE2) and nitric oxide, which cause the juxtaglomerular cells lining the afferent arterioles to release renin, activating the renin–angiotensin–aldosterone system, to increase blood pressure ...
Renal artery stenosis (RAS) is the narrowing of one or both of the renal arteries, most often caused by atherosclerosis or fibromuscular dysplasia.This narrowing of the renal artery can impede blood flow to the target kidney, resulting in renovascular hypertension – a secondary type of high blood pressure.
English: The renin–angiotensin system (RAS) or the renin–angiotensin–aldosterone system (RAAS). Start reading this schematic from the left, where it says "Decrease in renal perfusion (juxtaglomerular apparatus)".