Dual role of nitric oxide in pancreatic β-cells

An involvement of inducible nitric oxide (no) synthase (nos) in pancreatic β-cell degeneration during the process of type 1 diabetes has been well discussed. recently,there is growing evidence for pivotal roles of constitutive nos (cnos) in β-cells; the presence of nos1 and nos3 in pancreatic β-cells and the effects of low-concentration no,which is assumed to be derived from cnos,on β-cell functions have been reported. however,the roles of cnos-derived no in β-cells are still under debate. one of the reasons seems to be that no has multiple biological activities,which are dependent on its concentration. in β-cells,no has been shown to exert positive and negative regulation of insulin secretion and anti- and pro-apoptotic activities,which is likely to be dependent on concentrations. in this review article,we will describe the current understanding of the roles of no in pancreatic β-cells,especially focusing on cnos-derived no and its differential roles depending on concentrations. © the japanese pharmacological society.