STIMULATION OF SYNTHESIS OF GLYCOPROTEIN ENZYMES IN THE RAT UTERUS BY OESTRADIOL

Abstract

SUMMARY Glycoproteins from immature and immature, oestrogen-stimulated and adult rat uteri were isolated and analysed by chemical and gel electrophoretic methods. Esterase, acid phosphatase, alkaline phosphatase and peroxidase activities were found. Changes in electrophoretic mobilities of certain enzyme bands in polyacrylamide gel were also observed after hydrolysis of the preparations with neuraminidase. These latter observations and chemical analyses provide additional evidence of the carbohydrate nature of the enzymes. The influence of 17β-oestradiol on immature rat uteri caused a significant increase in total protein and sialic acid per uterus compared with controls. Oestrogen treatment also resulted in an increase in the total activity of esterase and acid and alkaline phosphatases per uterus, but there was no increase in specific activities. Observations of electrophoretic patterns of glycoprotein preparations from untreated and oestrogen-stimulated, immature uteri did not show the evolution to a more adult pattern by oestrogen stimulation. These studies show that stimulation with oestrogen increases the synthesis of glycoprotein in the immature rat uterus. Factors which are involved in the more intricate control of glycoprotein biosynthesis need to be elucidated.