Changes in enzymes of the uterus of the ovariectomized rat after treatment with oestradiol

Abstract

The sequence of changes in the activities of glucose 6-phosphate and phosphogluconate dehydrogenases has been determined in extracts of the endometrium and myometrium of the uteri of ovariectomized rats, untreated and at selected times after treatment with estradiol-17[beta] . The activity of the glucose 6-phosphate dehydrogenase in units/mg of soluble protein was significantly less than that of controls from 2 to 10 hr. after estradiol, but no difference was shown if the activity was calculated in terms of the insoluble residue of the uterus. By both methods of calculation a significant increase in the activities of both enzymes of both extracts was found at later times up to 48 hr. and a return to control values at 76 hr. The results of the determination of the specific activities of hexokinase of some of the extracts are reported. Trans-hydrogenase was determinable in extracts of myometrium but not of endometrium. Extracts of the adrenal glands of the same animals were analyzed in the same way to serve as control tissues. The enzyme activities exhibited no changes correlated with estradiol injection.