All of the following functions of vasopressin are mediated by v1 receptors, except
Correct Answer: Water reabsorption
Description: The mechanism by which vasopressin exes its antidiuretic effect is activated by V2 receptors and involves the inseion of proteins called water channels into the apical (luminal) membranes of the principal cells of the collecting ducts. Movement of water across membranes by simple diffusion is now known to be augmented by movement through water channels called aquaporins, and to date 13 (AQP0-AQP12) have been identified and water channels are now known to be expressed in almost all tissues in the body. The vasopressin-responsive water channel in the collecting ducts is aquaporin-2. V1A receptors mediate the vasoconstrictor effect of vasopressin, and vasopressin is a potent stimulator of smooth muscle in vitro. V1A receptors are also found in the liver and the brain. Vasopressin causes glycogenolysis in the liver, and, as noted above, it is a neurotransmitter in the brain and spinal cord. The V1B receptors (also called V3 receptors) appear to be unique to the anterior pituitary, where they mediate increased adrenocoicotropic hormone (ACTH) secretion from the coicotropes. Ref: Ganong&;s review of medical physiology,23rd edition, page: 666
Category:
Physiology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now