Effect of Uridine-Diphosphate-Glucose on Liver Glucuronyl Transferase Activity in Normal and in Fasting Rats

Abstract

The authors investigated the effect of uridinediphosphate glucose (UDPG) on the behaviour of liver glucuronyl transferase (GT) activity under different experimental conditions in 24 Sprague-Dawley rats.In the first series of experiments six rats received intraperitoneally 20 mg/kg of UDPG for 1 h; the second group was treated with 20 mg/kg of UDPG for 5 days and the third one with 50 mg/kg for 5 days. It was found that after UDPG treatment GT activity increases significantly, but with 50 mg/kg of UDPG the rise of enzyme activity is less important than with 20 mg/kg. 1-hour treatment does not influence GT activity. In the second series of experiments GT activity was investigated after a 72-hour fast in six rats and in six other rats receiving 20 mg/kg of UDPG 2 days before and during the 72-hour fast. Fasting caused an important decrease in GT activity, while enzyme activities did not change significantly in fasting rats treated with UDPG. The possible mechanisms by which UDPG exerts these effects are discussed.