Effects of in utero administration of phenobarbital on gamma-glutamyl transpeptidase.

The present study was undertaken to determine the effects of the in utero administration of phenobarbital (Pb) on gamma glutamyl transpeptidase (gamma-GTP) in rats. Female Wistar rats were bred to healthy adult males. On day 1 of gestation (evidenced by spermatozoa from vaginal smear) the pregnant rats were given 100 mg/kg phenobarbital (as the sodium salt) daily via the BioServ Liquid diet throughout gestation. Pair-fed controls were given the same volume of food as consumed by the experimental group. The offspring were sacrificed at birth and body, brain and liver weights determined. The pups born to the Pb treated mothers weighed significantly less than those born to the control mothers (4.77 and 6.60 g respectively). The brains and livers were homogenized in Tris buffered saline and assayed for gamma-GTP activity. Brain gamma-GTP activity was found to be 0.00807 u in the Pb group and 0.00670 u in the control group. We also examined the effects of chronic administration of Pb in adult rats and found no apparent effect on liver or brain gamma-GTP activity.