Rol de la Aquaporina-2 durante la proliferación y muerte celular en células del túbulo colector cortical renal

FLAMENCO P; RIVAROLA V; MELAMUD L; FERNANDEZ J; GALIZIA L; FORD P; CAPURRO C

Pucón

Congreso; 2do Congreso Iberoamericano de Ciencias Fisiológicas; 2009

Sociedad Latinoamericana de Ciencias Fisiológicas

We have reported that Aqp2 expression is critical for a rapid regulatory volume response in renal collecting duct cells. Changes in cell volume may act as signals for basic cell functions such as proliferation and apoptosis. The aim of this work was to investigate the role of AQP2 during cell cycle progression and apoptosis in renal cells. WT (not expressing AQPs) and AQP2-RCCD1 cells (transfected with AQP2) were used. Cell growth/death was evaluated by different approaches (flow cytometry, fluorescence videomicroscopy, DNA laddering, etc). Results demonstrate that AQP2 expression raises the rate of cell proliferation linked to an increased proportion of cells in GO/G1 phase. When apoptosis occurs three features distinguish AQP2 from WT cells: (i) the rate of apoptosis is significantly increased; (ii) the pharmacological blockade of volume regulatory K+ and Cl- channels prevented apoptosis only in AQP2 cells and (iii) the water permeability is reduced before DNA degradation only in AQP2 cells. These results suggest that under cell growth/death changes in cell volume occurs and AQP2 would act as a sensor leading to a coordinated activation of specific mechanisms controlling these events.