Effects of progressive hyperglycemia on ovarian structure and function in the spontaneously diabetic Chinese hamster.

The effect of the progressive hyperglycemic condition on ovarian follicular maturation was studied in control, moderate (160-350 mg/dl blood glucose), and overt (greater than or equal to 350 mg/dl blood glucose), spontaneously diabetic Chinese hamsters. Match-paired (age, sex, and weight) control and diabetic animals were sacrificed at specific intervals during the development of the diabetic condition; the ovaries were collected and morphometrically analyzed for changes in ovarian follicular growth relative to blood glucose levels. Follicles were classified according to size, number, and condition. The total number of primary (100-200 micrometers diameter) and secondary (200-350 micrometers diameter) follicles was reduced in both moderate and overt diabetic females as compared with controls. The percentage of viable (i.e., nonatretic) follicles was greatly reduced in the secondary follicle class of overt diabetic animals as compared with controls. No significant differences were observed in the numbers of viable tertiary (i.e., greater than or equal to 350 micrometers diameter) follicles in any of the diabetic animals as compared with controls. The percentage of atretic, secondary follicles was greatly increased in the overt diabetic group as compared with controls. These data indicate that the progressive hyperglycemia associated with diabetes in the Chinese hamster induces a severe depression of normal follicular recruitment resulting in an impaired reproductive performance in this species.