Pancreatic exocrine acinar cells in NOD mice, an animal model of Type 1 diabetes, were examined in relation to the numbers of zymogen granules and the incorporation of leucine-³H.
(1) There were no differences between the acinar cells in NOD mice aged three weeks and those in age-matched ICR mice with regard to the numbers of zymogen granules and the incorporation of leucine-³H.
(2) Acinar cells in NOD mice aged three to five months, which were accompanied by insulitis, showed the depletion of zymogen granules and incorporation of leucine-³H, mildly in the normoglycemic group and markedly in the hyperglycemic one, when compared with those in agematched ICR mice.
(3) The hyperglycemic NOD mice showed the marked depletion of acinar zymogen granules in the fed state, and, a prominent delay in the recovery of the zymogen granules after cerulein stimulation was undertaken.
(4) The decreased rate of protein synthesis in the exocrine acinar cells is thought to be one of the main causes of the decreased numbers of zymogen granules in NOD mice accompanied by insulitis.