Ultrastructural characteristics of the pancreatic acinar cells in the diabetes-prone BB rat

BB랫드의 췌장 샘포세포의 미세구조적 특징

Functional and morphological characteristics of the exocrine pancreas in genetic model BB rat of insulin dependent diabetes medllitus(IDDM) were carried out. Wistar rat was used as control animal. Flow rate of pancreatic juice, output of amylase and protein, and plasma glucose and insulin levess were examined. Also light and ultrastructural characteristics of the exocrine pancreas were observed. Pancreatic flow rate, output of amylase and protein, and insulin level were lower;glucose level was higher comparing with those of the control Wistar rat. In Wistar rat, exocrine pancreas was typical light microscopically. Zymogen granules and cell organelles were well developed in fine structure. Cell size of the periinsular acini was larger, and number of zymogen granules were more than those of the teleinsular acini. Most acinar cells were dark cells which containe well-developed RER in their cytoplasm. On the other hand, some light cells which have the dilated RER cisterns were found. In BB rat exocrine pancreas, cell size of per-and tele-insular acini similar to that of Wistar rat. The number of light cells occupied 40-50% compairing with that of Wistar rat. Zymogen granules were lower in number than that of Wistar rat and divied into three types in morphological characteristics ; type I showing normal structure, type II showing the wide hallo and small electron dense core in center of the zymogen granule and type III not having the electron dense core in the zymogen granule. The present ratio of type I, type II and type III are less than 5%, 30-40% and more than 50%, respectively.