Question

summarize the mechanism used by kidneys to to control glomerular filtration rate during low arterial pressure

Answer 1

The low arterial pressure causes the decreased renal blood flow. The decreased renal blood flow triggers the juxtaglomerular cells of the kidney to convert the prorenin into the renin and secrete them into the blood.The renin in the bloodstream acts upon the liver and convert the Angiotensinogen into angiotensin I.Further, angiotensin I gets converted into the angiotensin II. Angiotensin II acts upon the blood vessels and causes the vasoconstriction. On the other hand angiotensin II triggers the release of aldosterone from the adrenal gland, which causes the reabsorption of sodium ions by the kidney tubules and release of water into the blood,thus increases the blood volume and increases the mean arterial pressure.