FIGURE 7.

Validation of the PKA-dependent mechanism in primary astrocytes. Cell surface biotinylation of primary rat astrocytes exposed to hypotonic stimulus in the presence and absence of PKA inhibition and analysis of endogenous AQP4 surface expression is shown. In the absence of the inhibitor, AQP4 surface expression increased 2.2-fold between 340 and 85 mosm/kg of H₂O, n = 3, p = 0.008. In the presence of the inhibitor, AQP4 surface expression did not change significantly between 340 and 85 mosm/kg of H₂O, n = 3,p = 0.24. All data are presented as mean ± S.E. n.s., not significant.