Progesterone and glucose metabolism in the female rat adipocyte: effect on hexokinase activity.
Progesterone decreases the oxidation of 2-deoxyglucose and glucose through the pentose-phosphate pathway in isolated female rat adipocytes and, therefore, the effect of this steroid incubation in vitro, progesterone decreased total hexokinase activity but did not affect the isoenzyme-I activity. Progesterone had no direct effect on fat cell cytosol hexokinase and its action on glucose oxidation was not affected by variations in the concentration of Mg2+, the cofactor of hexokinase. Our data suggest that the decreased activity of hexokinase in the presence of progesterone is due to a decrease in the activity of the insulin-sensitive isoenzyme-II. This results from the steroid acting at a step beyond enzyme activation and may be mediated by a feedback mechanism.
D000273:Adipose Tissue / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006593:Hexokinase / Q000378:metabolism*; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000378:metabolism*; D008274:Magnesium / Q000494:pharmacology; D011374:Progesterone / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D007527:Isoenzymes; D011374:Progesterone; D006593:Hexokinase; D008274:Magnesium; D005947:Glucose