Glycemia and immunohistochemical changes in the endocrine pancreas of the turtle Chrysemys dorbigni treated with streptozotocin

ABSTRACT

The diabetogenic action of streptozotocin (SZ) was inbestigated in the turtle Chrysemys dorbigni after a 1-or 14-day fast. SZ (130 or 250 mg/Kg) was inected intravenously, and blood glucose and plasma insulin were measured. Pancreatic endocrine cells were stained immunohistochemically by the immunoperoxidase avidin-biotin-peroxidase complex method. Only 14% of the SZ-treated turtles showed hyperglycemia. Prolonged fasting did not increase the percentage of hyperglycemic animals. In control turtles, insulin (ß-, glucagon (alfa)-and somatostatin (delta)-immunoreactive cells were detected in increasing order of frequency. The qualitative changes seen in cells from the hyperglycemic SZ-treated turtles were more evident in ß and delta cells