Low dose ouabain stimulates NaK ATPase α1 subunit association with angiotensin II type 1 receptor in renal proximal tubule cells.

Our laboratory has recently demonstrated that low concentrations of ouabain increase blood pressure in rats associated with stimulation of NaK ATPase activity and activation of the Src signaling cascade in NHE1-dependent manner. Proteomic analysis of human kidney proximal tubule cells (HKC11) suggested that the Angiotensin II type 1 receptor (AT1R) as an ouabain-associating protein. We hypothesize that ouabain-induced stimulation of NaK ATPase activity is mediated through AT1R.