Question

Enzyme 'Renin' is secreted by

• A. Cells of the stomach
• B. Cells of the intestine
• C. The cortical cells of the kidney
• D. The cells of juxtaglomerular apparatus of the kidney

Answer 1

The correct option is D The cells of juxtaglomerular apparatus of the kidney

The juxtaglomerular apparatus (JGA) plays a complex regulatory role. A fall in glomerular blood flow/ glomerular blood pressure/ glomerular filtration rate (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 sodium 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.

Therefore, the correct answer is option D.