Activation of the Metabolic Sensor AMP-Activated Protein Kinase Inhibits Aquaporin-2 Function in Kidney Principal Cells.

Activation of the Metabolic Sensor AMP-Activated Protein Kinase Inhibits Aquaporin-2 Function in Kidney Principal Cells. Am J Physiol Renal Physiol. 2016 Aug 17;:ajprenal.00308.2016 Authors: Al-Bataineh MM, Li H, Ohmi K, Gong F, Marciszyn A, Naveed S, Zhu X, Neumann D, Wu Q, Cheng L, Fenton RA, Pastor-Soler NM, Hallows KR Abstract Aquaporin-2 (AQP2) is essential to maintain body water homeostasis. AQP2 traffics from intracellular vesicles to the apical membrane of kidney collecting duct principal cells in response to vasopressin (AVP), a hormone released with low intravascular volume, which causes decreased kidney perfusion. Decreased kidney perfusion activates AMP-activated kinase (AMPK), a metabolic sensor that inhibits the activity of several transport proteins. We hypothesized that AMPK activation also inhibits AQP2 function. These putative AMPK effects could protect interstitial ionic gradients required for urinary concentration during metabolic stress when low intravascular volume induces AVP release. Here we found that short-term AMPK activation by treatment with 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR; 75 min) in kidney tissue prevented baseline AQP2 apical accumulation in principal cells but did not prevent AQP2 apical accumulation in response to the AVP analog desmopressin (dDAVP). Prolonged AMPK activation prevented AQP2 cell membrane accumulation in response to forskolin in mouse collecting duct mpkCCD...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Tags: Am J Physiol Renal Physiol Source Type: research