Hyperglycaemia induced by glucose infusion in the unrestrained pregnant rat: effect on body weight and lipid synthesis in post-mature fetuses.

Mild hyperglycaemia was induced in unrestrained pregnant rats from day 20.5 to day 23.5 of pregnancy, using a continuous glucose infusion. Control rats were infused with distilled water. In post-mature fetuses from glucose-infused rats, raised plasma glucose and insulin concentrations were related to increased body weight (6.03 +/- 0.07 g) and total carcass fat (2.02 +/- 0.04% of fresh weight) compared with control fetuses of the same age (5.35 +/- 0.07 and 1.5 +/- 0.04 g, respectively). Concurrently, the rate of lipogenesis in the carcass, estimated from the incorporation of tritium from tritiated water into fatty acids, was significantly increased in fetuses from glucose infused rats compared with control rats (6.00 +/- 0.34 versus 2.62 +/- 0.27 and 3H2O X h-1 X g tissue-1, respectively.