Polyarteritis nodosa-like inflammatory vascular changes in the pancreas and mesentery of rats treated with streptozotocin and nicotinamide.

Pancreatic endocrine tumours and inflammatory vascular changes resembling those of human polyarteritis nodosa occurred simultaneously in male Holtzman rats after a single injection of streptozotocin and two injections of nicotinamide. The histomorphological appearance of the arterioles resembled that seen in vascular diseases of immunopathogenetic origin. The proximity of the vascular lesions to the hormone-producing tumour suggested that the tumour-related hormone production induced the development of the panarteritis. Streptozotocin-nicotinamide-induced vasculitis in rats was histologically similar to human polyarteritis nodosa. It may therefore provide a good animal model for the human disease.