Regulation of corticosterone metabolism in liver cell fractions in young and adult rats: cofactor requirements, effects of stress and phenobarbital treatment.
Corticosterone metabolism was studied in the 10,000 X g supernatant fraction of the liver homogenate supplemented with cofactors (NADH, NADPH), or with the system participating in NADPH synthesis. NADPH was more effective than NADH for the degradation of the A ring and the side chain of corticosterone. The rate of reduction of the A ring, in both the supernatant and the sediment, was higher in adult than in infant rats. The rate of metabolism of the side chain did not change during development in the supernatant, but it was lower in the sediment from adult than from young animals. Corticosterone metabolism was also studied in infant and adult rats, after recurrent stressful stimulation or the repeated administration of phenobarbital, in both liver homogenate fractions, supplemented by the NADPH-regenerating system. Both stress and phenobarbital administration reduced the rate of corticosterone side chain and A ring metabolism in the liver of 7-day-old young. In adult animals, the rate of corticosterone metabolism was unaffected by stress, but the administration of phenobarbital raised the rate of metabolism of the corticosterone side chain in the sediment fraction obtained by centrifugation at 10,000 X g.
D000375:Aging; D000818:Animals; D005591:Chemical Fractionation; D003067:Coenzymes / Q000494:pharmacology*; D003345:Corticosterone / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009243:NAD / Q000494:pharmacology; D009249:NADP / Q000494:pharmacology; D010634:Phenobarbital / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013312:Stress, Physiological / Q000378:metabolism*; D014018:Tissue Distribution
D003067:Coenzymes; D009243:NAD; D009249:NADP; D003345:Corticosterone; D010634:Phenobarbital