Renovascular hypertension (or "renal hypertension") is a syndrome which consists of high blood pressure caused by the kidneys hormonal response to narrowing of the arteries supplying the kidneys (renal artery stenosis). When functioning properly this hormonal axis regulates blood pressure. Due to low local blood flow, the kidneys mistakenly increases blood pressure of the entire circulatory system. It is a form of secondary hypertension - a form of hypertension whose cause is identifiable.
Cause: Narrowing of the arteries supplying the kidneys causes a low perfusion pressure which is detected by the juxtaglomerular apparatus (via the juxtaglomerular cells, which act as baroreceptors; located on the afferent arteriole wall). This leads to renin secretion that causes the angiotensinogen conversion to angiotensin I. Angiotensin I then proceeds to the lung where it is converted to Angiotensin II via Angiotensin Converting Enzyme (ACE). Angiotensin II causes vasoconstriction and aldosterone release leading to water and sodium retention and potassium depletion. The increased blood volume and vessel constriction contributes to increased blood pressure which can lead to hypertension.
Other articles related to "renovascular hypertension, renovascular":
... Harrison's Manual of Medicine Renovascular Disease - Renal Artery Stenosis www.emedicine.com ...