Gestational diabetes in the BHE rat: influence of dietary fat.

Two studies were performed to assess the effect of fat feeding on glucose tolerance before, during, and after gestation of BHE rats. In the first study 5% or 22% fat diets were fed from 3 weeks before mating until after gestation. In the second study, these diets were fed from weaning until 400 days of age. Glucose tolerance before and after gestation was not affected by diet in the short-term study. At 19 days' gestation, glucose tolerance had deteriorated in the pregnant rats that were fed with 22% fat diet. In the long-term study, abnormal glucose tolerance was observed before mating in rats that were fed the 22% fat diet. Tolerance improved during gestation and post partum, but still was not normal. Fertility and pup survival were significantly (50%) reduced in rats that were fed the 22% fat diet. These findings suggest that either short-term or long-term feeding of a 22% fat diet to BHE rats results in a model for human gestational diabetes that might be worthy of further study.