| Abstract: | The Wistar Diabetic Fatty rat (WDF fafa) is a con-genic strain of the Wistar Kyoto rat. Studies using blood glucose reveal that only fatty male (not female) WDF rats spontaneously develop hyperglycemia when fed a stock diet Blood glucose values have not provided consistent results for evaluation of glycemic status in fatty male WDF rats. Zucker fatty (fafa) rats, while sharing the fa gene and the development of hyperinsulinemia and hyperlipemia, do not spontaneously become hyperglycemic. In order to examine strain differences and the effects of age on long-term average glycemic status in WDF and Zucker rats, glycated hemoglobin (GHb) was analyzed. Glycated hemoglobin was measured in male lean and obese WDF and Zucker rats at 2,3,6, and 12 months of age. Nonfasted plasma glucose was measured in male lean and obese WDF rats at 2, 3, 6, and 12 months of age and in lean and obese Zucker rats at 3, 6, and 12 months of age. Plasma insulin was measured in lean and obese WDF and Zucker rats at 3, 6, and 12 months of age. Obese WDF rats had significantly elevated GHb compared to lean controls at 3, 6, and 12 months of age. Glycated hemoglobin was substantially above the normal range (3.8-6.5%) at 3 months of age (14.1%). Glycated hemoglobin significantly declined in the obese WDF rats between 6 and 12 months of age. Nonfasted plasma glucose was significantly elevated in the obese WDF rats at 3 months (14.1 ± 2.1 mM/L) and 6 months of age (16.2 ± 2.3 mM/L) compared to lean controls. At 12 months of age there was no difference in plasma glucose between obese and lean WDF rats. Obese and lean Zucker rats had similar levels of GHb and plasma glucose at all ages. In conclusion, GHb provides more integrated data for classifying disease status of WDF rats and evaluation of potential long-term complications associated with hyperglycemia. |
