Fig. 14.

Protein kinase C (PKC) and adenosine monophosphate kinase (AMPK) did not change phosphorylation of AQP2 at serine 256 in rat inner medulla (IM). A: representative Western blot showing AQP2 abundance and phosphorylated AQP2 in rat IM with phorbol dibutyrate (PDBu) (PKC activator), metformin (Met; AMPK stimulator), or both for 30 min. Brackets indicate AQP2 glycosylated protein between 35 and 45 kDa and arrows indicate unglycosylated protein at 29 kDa. Samples from a different rat were loaded into each lane. B: bar graph showing the ratio of the band densities of phosphorylated AQP2 to total AQP2 abundance. Bars  = means ± SE; results were not significantly different from the isotonic control group without PDBu and metformin. n = 6 rats/condition. Ctrl, control.