EINFLUSS VON CYCLUS UND EXOGENER HORMONZUFUHR AUF STOFFWECHSELVORGÄNGE DES RATTENUTERUS

Abstract

ABSTRACT The first significant increase of weight, RNA and protein was observed in the uterus of spayed rats twelve hours after the intraperitoneal administration of a single dose of 1 μg oestradiol. There was no significant increase of DNA. At the same time the activities of glucose-6-phosphate dehydrogenase, fructose-1,6-diphosphate aldolase, isocitrate dehydrogenase and leucine aminopeptidase had increased significantly. Twentyfour hours after the injection the augmented values began to decline. Three injections of 1 μg oestradiol, given at 24 hour intervals obtained similar changes, the only difference being that these changes were more marked and that a DNA increase was also observed. The augmentation of protein, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and fructose-1,6-diphosphate aldolase content of cells induced by repeated oestradiol injections was inhibited partly by 1 mg progesterone when administered together with the last dose of oestradiol. During the normal oestrus cycle of the rat uterus an increase of uterine weight, DNA and RNA content and also of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and 1,6-diphosphate aldolase activities was observed, whereas isocitrate dehydrogenase, malate dehydrogenase and leucine aminopeptidase did not change significantly. It would appear that the changes after exogenous hormone administration reflect those of the normal cycle as regards both their extent and timing. The importance of these findings in connection with hormone-induced pathways of uterine metabolism is discussed.