Effect of age and sex on the inducibility of hepatic microsomal 4-nitrophenol UDP-glucuronyltransferase activity in rats.
In this report, we examined the effect of age and sex of Long-Evans rats on the inducibility of 4-nitrophenol glucuronyltransferase activity in liver microsomes of animals treated with phenobarbital, dexamethasone, or 3-methylcholanthrene. Glucuronyltransferase activity in control male liver microsomes was approximately 50-75% higher than that in control female liver microsomes. Treatment with sodium phenobarbital (i.p., 75 mg/kg/day) for 3-4 days increased glucuronyltransferase activity by approximately 100% and 60% in liver microsomes from adult female and male rats, respectively, but did not influence this activity in liver microsomes from immature female and male rats. Treatment with dexamethasone (i.p., 75 mg/kg/day) for 3-4 days increased glucuronyltransferase activity by approximately 4-fold in liver microsomes from immature female rats but markedly decreased this enzyme activity in liver microsomes from adult female rats, adult male rats, and immature male rats. Treatment with 3-methylcholanthrene (i.p., 25 mg/kg/day) for 3-4 days increased glucuronyltransferase activity by approximately 10- to 13-fold in liver microsomes from immature female rats, adult female rats, and adult male rats, but only increased this enzyme activity by approximately 1-fold in liver microsomes from immature male rats. In conclusion, the extent of induction of hepatic microsomal glucuronyltransferase activity for 4-nitrophenol is affected dramatically by the age and sex of the animals.
Zhu
B T
BT
Department of Chemical Biology and Pharmacognosy College of Pharmacy, Rutgers State University of New Jersey, Piscataway 08855-0789, USA.
Suchar
L A
LA
Gwynne
M
M
Huang
M T
MT
D000375:Aging / Q000378:metabolism*; D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology; D004790:Enzyme Induction / Q000187:drug effects; D005260:Female; D014453:Glucuronosyltransferase / Q000096:biosynthesis* / Q000097:blood* / Q000378:metabolism; D008297:Male; D008748:Methylcholanthrene / Q000494:pharmacology; D008862:Microsomes, Liver / Q000187:drug effects* / Q000201:enzymology*; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012737:Sex Factors
D008748:Methylcholanthrene; D003907:Dexamethasone; D014453:Glucuronosyltransferase; D010634:Phenobarbital