AQP2-Induced Acceleration of Renal Cell Proliferation Involves the Activation of a Regulatory Volume Increase Mechanism Dependent on NHE2.

We have previously shown in renal cells that expression of the water channel Aquaporin 2 (AQP2) increases the rate of cell proliferation by shortening the transit time through the S and G /M phases of the cell cycle. This acceleration is due, at least in part, to a down-regulation of regulatory volume decrease (RVD) mechanisms when volume needs to be increased in order to proceed into the S phase. We hypothesize that in order to increase cell volume, RVD mechanisms may be overtaken by regulatory volume increase mechanisms (RVI).