Question

Which of the following is most appropriate regarding kidney function regulation? Stimulation of

• A. Renin-angiotensin mechanism decreases the Glomerular Filtration Rate (GFR) while atrial natriuretic factor increase GFR
• B. Renin-angiotensin mechanism increase GFR while atrial natriuretic factor decreases GFR
• C. Renin-angiotensin mechanism and atrial natriuretic factor both increase the GFR
• D. Renin-angiotensin mechanism and atrial natriuretic factor both decrease the GFR

Answer 1

Answer: (B)

Renin Angiotensin mechanism increases the Glomerular Filtration Rate (GFR), while atrial natriuretic factor decreases GFR. A reduced blood pressure causes reduced GFR, result in release of renin by juxta glomerular cells. Renin converts angiotensinogen into angiotensin-II and angiotensin-II. The latter increases the BP by constriction of arterioles and thus increase GFR. ANF is produced by atria of heart and results in decrease blood pressure by reducing $H_{2}O$ , Na and adipose loads on circulatory system.