renin-angiotensin system

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re·nin-an·gi·o·ten·sin sys·tem

a selective regulator of the aldosterone biosynthetic pathway that acts by increasing aldosterone production and sodium retention as a result of volume depletion, with resulting increased renin production in the kidney and conversion of angiotensin I in the plasma to angiotensin II.

renin-angiotensin system

the regulation of sodium balance, fluid volume, and blood pressure. In response to reduced perfusion, renin is secreted, which hydrolyzes a plasma globulin to release angiotensin I, which is rapidly hydrolyzed to angiotensin II, a powerful vasoconstrictor; angiotension II also stimulates aldosterone secretion, which causes sodium retention, an increase in blood pressure, and restoration of renal perfusion, which shuts off the signal for renin release (negative feedback). Angiotensin-converting enzyme also deactivates bradykinin, a vasodilator. Also called renin-angiotensin-aldosterone system.
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Renin-angiotensin system

re·nin-an·gi·o·ten·sin sys·tem

(RAS) (rē'nin-an-jē-ō-tensin sistĕm)
Selective regulator of the aldosterone biosynthetic pathway that acts by increasing aldosterone production and sodium retention due to volume depletion.

renin

a proteolytic enzyme synthesized, stored and secreted by the juxtaglomerular cells of the kidney; it plays a role in regulation of blood pressure by catalyzing the conversion of the plasma glycoprotein angiotensinogen to angiotensin I. This, in turn, is converted to angiotensin II by an enzyme that is present in relatively high concentrations in the lung. Angiotensin II is one of the most potent vasoconstrictors known, and also is a powerful stimulus of aldosterone secretion.

renin-angiotensin system
renin, secreted by the juxtaglomerular apparatus, activates the precursor angiotensinogen. This liberates angiotensin I, then angiotensin II, a vasoconstrictor and stimulant to the secretion of aldosterone.
big renin
a relatively inactive protein with a higher molecular weight than normal renin, which is activated after exposure to low pH or to proteolytic enzymes.
References in periodicals archive ?
Plasma 25-hydroxyvitamin D and regulation of the renin-angiotensin system in humans.
Blockade of the renin-angiotensin system for the primary prevention of diabetic nephropathy.
Raizada, "A current view of brain renin-angiotensin system: is the (pro)renin receptor the missing link?
The ACE works in the renin-angiotensin system to increase blood pressure.
New frontiers in the intrarenal Renin-Angiotensin system: a critical review of classical and new paradigms.
The latter two are a part of the renal vasodilator system, whereas the renin-angiotensin system represents the renal vasoconstrictor, with the vasodilator systems modulating vasoconstrictive effects of angiotensin II on one hand, and angiotensin II stimulating the secretion of vasodilatory components on the other, which prevents substantial increase in the renal vascular resistance.
1,25-Dihydroxyvitamin D3 is a negative endocrine regulator of the renin-angiotensin system.
Inhibition of the renin-angiotensin system with angiotensin-converting enzyme inhibitors or angiotensin II receptor antagonists is particularly effective at reducing the albumin excretion rate, but whether these classes of drugs are more beneficial in patients with microalbuminuria remains to be determined.
In general, only SD receiving maitake SX, not the two drugs, showed decreased activity of the renin-angiotensin system and increased NO system activity compared with control under the conditions examined.
Studies have demonstrated that renin-angiotensin -aldosterone system (RAAS) plays important roles in the regulation of myocardial collagen metabolism and the occurrence of myocardial fibrosis [1, 2].
Allikmets24 suggested that the importance of the Renin-angiotensin system (RAS) in blood pressure regulation is well established.
6) The renin-angiotensin system (RAS) is an important link between MS and cardiovascular diseases.