Phosphorylation of neuronal and endothelial nitric oxide synthase in the kidney with high and low salt diets

Abstract

Background: Renal nitric oxide (NO) synthesis increases with increasing salt intake, however, the mechanisms underlying this are poorly understood. We hypothesized that activating or inhibitory phosphorylation of neuronal and endothelial nitric oxide synthase (nNOS, eNOS) regulates renal NO production in response to altered dietary salt. Methods: Sprague-Dawley rats were fed low, normal or high salt diets for 12 h or 2 weeks, and kidney NOS phosphorylation was analyzed by Western blot using phosphopeptide antibodies against the sites nNOS-Ser1412, nNOS-Ser847, eNOS-Ser1176 and eNOS-Thr494. Results: At 12 h, total nNOS increased 1.4-fold (p < 0.01) in the high salt group and decreased by 26% ..