Histological and Autoradiographic Studies of the Islets of Mice Injected with Insulin Antibody

Abstract

Young adult male mice were injected intraperltoneally twice daily with the globulin fraction of anti-insulin sera. Control mice recieved injections of the same fraction from guinea pigs immunized with Freund''s adjuvant only. Blood glucose levels in the mice injected with insulin antibodies were continuously maintained over 250 mg/100 ml. Mice were killed before and at 1, 3, 6, 10 and 15 days after the injections started. Thy-midine-H-3 was injected subcutaneously 2 hrs. before killing. The following observations were made: Beta cells quickly lost their granules and remained degranulated throughout the period of injections of insulin antibodies. Swelling of the Golgi complex and other histological evidence of increased cellular activity were present. Neutrophils, eosinophils and monocytes accumulated around the islets in the mice injected with antibody. In the control mice the number of labeled beta cell nuclei (radioactive index) ranged from 7-25 per 3,000 nuclei of beta cells. Labeled beta cells were scattered throughout the islets. Alpha cells showed a lower radioactive index, 1-3 per 1,000 nuclei. In the mice injected with antibody the radioactive index was within the normal range on the 1st day, reached a peak in mice killed on the 3rd day and subsequently progressively declined in spite of the substained hyperglycemia.