Inhibition of nitric oxide formation by aminoguanidine: an attempt to prevent insulin-dependent diabetes mellitus.

1. Insulin-dependent diabetes mellitus is an autoimmune disease leading to pancreatic beta-cell destruction, an event that may, at least partially, be induced by the formation of nitric oxide. 2. Under the influence of cytokines, the enzyme nitric oxide synthase is induced. 3. Blockage of the inducible form of nitric oxide synthase has been found to protect against insulin-dependent diabetes mellitus in some animal models. 4. Aminoguanidine has been found to be a fairly specific inhibitor of cytokine-inducible nitric oxide synthase. 5. Aminoguanidine may reduce the blood flow to the pancreatic islets in vivo and, at higher concentrations, also impair insulin secretion by the beta-cells,--which may make the compound less useful in attempts to prevent insulin-dependent diabetes mellitus.