Which one amongst the following is a powerful vasoconstrictor ?
Answers
Answer:
Angiotensin II
Angiotensin II being a powerful vasoconstrictor increases the glomerular blood pressure and thereby glomerular filtration rate. Angiotensin II also activates the adrenal cortex to release aldosterone
Explanation:
Osmoreceptors in the body are activated by changes in blood volume, body fluid volume and ionic concentration. A fall in glomerular blood flow/glomerular blood pressure/GFR can activate the JG cells to release renin which converts angiotensinogen in blood to angiotensin I and further to angiotensin II. Angiotensin II, being a powerful vasoconstrictor, increases the glomerular blood pressure and thereby GFR. Angiotensin II also activates the adrenal cortex to release aldosterone. Aldosterone causes reabsorption of Na
+
and water from the distal parts of the tubule. This also leads to an increase in blood pressure and GFR. This complex mechanism is generally known as the Renin-Angiotensin mechanism.