RAAS Inhibitors concept in pharmacology for NEET/AIIMS/USMLE/FMGE/PLAB скачать в хорошем качестве

RAAS Inhibitors concept in pharmacology for NEET/AIIMS/USMLE/FMGE/PLAB

RAAS Inhibitors concept in pharmacology for NEET/AIIMS/USMLE/FMGE/PLAB • The renin-angiotensin system begins with production of angiotensinogen by liver, which is metabolized by renin from juxtaglomerular cells of kidney to angiotensin I (AT-I). • AT-I is further metabolized by angiotensin converting enzyme (ACE) into angiotensin II (AT-II). • AT-II has diverse target and causes vasoconstriction and constriction of glomerular efferent and afferent arterioles, and increases release of aldosterone, vasopressin and catecholamines (inhibits NE reuptake in synapse and stimulates catecholamine release in adrenals) and induces thirst and anorexia. In the nephron, AT-II stimulates Na/H exchanger in PCT and Na/K/2Cl transporter in thick ascending limb of loop. • Angiotensin II is further metabolized into angiotensin III, which further forms angiotensin IV; both steps being catalysed by aminopeptidases. Angiotensin III has effects like angiotensin II, whereas angiotensin IV enhances cognition. Hence angiotensin IV analogs are under development for treatment of Alzheimer’s disease. • RAS can be targeted at various levels by inhibiting renin (renin inhibitors), ACE (ACE inhibitors) and AT-1 receptors (angiotensin receptor blockers). The common effect seen will be a reduction in blood pressure, loss of solutes and water and retention of potassium i.e. hyperkalemia.