ADH causes increased reabsorption of water from the filtrate as the filtrate pas

Question

ADH causes increased reabsorption of water from the filtrate as the filtrate passes through the collecting duct toward the renal pelvis. The mechanism associated with ADH’s action is

A. insertion of water channels in the apical membrane of the cells of the collecting duct, increasing its permeability to water.

B. insertion of larger water channels (channels with greater diameters) into the apical membrane of the collecting duct, increasing the flow rates through the epithelium.

C. Increasing the number of Na+,K+-ATPases in the basolateral membrane of the epithelium while simultaneously increasing the number of sodium channels in the apical membrane, thereby increasing Na+ reabsorption with water following as a consequence.

D. All of the above.

E. None of the above.

Explanation / Answer

Choice A is correct.

Reason: The ADH or anti-diuretic hormone or vasopressin as a peptide neurohormone which prevents release of water from the urine by increasing its uptake and reabsorption in the renal tubules. The ADH promotes up-regulation in the number of water channels in the apical part of the collecting duct and renal tubule thus promoting re-absorption of water. This is actually a transcriptional and translational control of ADH over the renal apical cells of the system. Further, the permeability of the water is increased in the renal epithelium so that large amount of water might be re-absorbed and transferred to the circulation. This helps in maintenance of blood volume of the body.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.