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Aquaporin-2 membrane targeting: still a conundrum
Emma T B Olesen1,2, Robert A Fenton3
1Department of Biomedical Sciences, Faculty of Health Sciences, Copenhagen University, Copenhagen, Denmark; etbo@sund.ku.dk.
American Journal of Physiology. Renal Physiology
|February 10, 2017
Summary
Arginine vasopressin (AVP) regulates aquaporin-2 (AQP2) in kidney cells, crucial for water balance. Emerging research suggests this AQP2 trafficking may occur independently of cyclic adenosine monophosphate (cAMP).
Area of Science:
- Nephrology
- Molecular Biology
- Cell Biology
Background:
- The antidiuretic hormone arginine vasopressin (AVP) controls aquaporin-2 (AQP2) targeting to the apical membrane of kidney collecting duct principal cells.
- This trafficking is vital for maintaining the body's water homeostasis.
- Cyclic adenosine monophosphate (cAMP) has been considered a key mediator in this process.
Purpose of the Study:
- To review the role of cAMP in AVP-mediated AQP2 trafficking.
- To discuss the emerging evidence for cAMP-independent AQP2 trafficking pathways.
Main Methods:
- Literature review of studies on AVP, AQP2, and cAMP signaling.
- Analysis of current research on V2R-mediated cellular mechanisms.
Main Results:
- AVP-stimulated AQP2 targeting is traditionally linked to cAMP.
- Emerging data indicates that V2R activation can promote AQP2 trafficking through cAMP-independent pathways.
Conclusions:
- While cAMP plays a significant role, it may not be the sole mediator of AVP-induced AQP2 trafficking.
- Further research is needed to fully elucidate the mechanisms of cAMP-independent AQP2 regulation.
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