Endothelium-derived relaxing factor, nitric oxide

The endothelium-derived relaxing factor nitric oxide (EDRF/NO) is a labile, endogenous vasodilator that is important in the control of systemic vascular tone. This review focuses on the effects of EDRF/NO on glomerular mesangial cells in vitro and on the role of EDRF/NO in mesangial and glomerular physiology and pathophysiology in vivo. It was concluded that EDRF/NO can stimulate increases in cGMP, inhibit mesangial cell contraction, and inhibit growth factor-induced proliferation of mesangial cells in culture. Furthermore, incubation with endotoxin or cytokines stimulates mesangial cells to produce EDRF/NO, via an inducible NO synthase enzyme. Therefore, it is likely that NO could play a role in the inflammatory response within the glomerulus. Finally, recent studies providing evidence that EDRF/NO is functional within the glomerulus in vivo, especially during endotoxemia and inflammation are also reviewed.