Polyarteritis nodosa induced in arteriosclerotic, male and female breeder rats by chronic alloxan diabetes.

Male and female virgin rats and breeder rats with naturally-occurring diabetes, hypertension and arteriosclerosis, were made severely diabetic with a single, subcutaneous injection of alloxan (10 mg/100 g b.w.), after an 18 h fast. During five months of unrelenting diabetes, some animals became obese while others became emaciated. Only the emaciated animals survived but they were blind, their adrenal glands were hemorrhagic, hypertrophied and thrombosed, thymi involuted, kidneys swollen, hearts reduced in size while testes and ovaries were atrophic. Serum CPK, SGOT and SGPT were elevated concomitant with extensive cardiovascular damage, hepatic steatosis and generalized catabolism. Circulating triglycerides and free fatty acids were markedly elevated with total cholesterol only slightly increased. BUN and serum calcium levels were also greatly elevated. Sub-normal Cmpd. B levels indicated impaired adrenal steroidogenesis. Virgin rats developed arteriosclerosis and male and female breeder rats showed exacerbation of their pre-existing aortic sclerosis as well as P.A.N. lesions in their small-sized arteries. It is believed that severe diabetes causes exacerbation of the endogenous hormonal milieu resulting from abnormal hypothalamic-pituitary-adrenal function induced by repeated breeding, which conditions the connective tissue components of the arterial wall of rats toward accelerated degenerative changes.