COMPARISON OF OESTROGEN-INDUCED GLYCOGENESIS IN THE UTERUS OF THE RAT, RABBIT AND SHEEP

Abstract

ABSTRACT Essentially similar 2- to 3-fold increases in glycogen concentration were observed in uteri of rats, rabbits and sheep in the first six to ten hours after administration of 17β-oestradiol. Rats and rabbits were treated with alloxan to assess the effect of high circulating levels of glucose upon uterine glycogen and upon uterine glucose shifts. Uterine glycogen was elevated to a level almost as high as that achieved under oestrogen stimulation. Oestrogen administration caused a further increase in glycogen concentration. Free uterine glucose was measured in each species to see whether an increase in glucose availability occurred. The relative expansion in glucose space was compared to chloride space (used as an index of extracellular volume) to determine if there was an influx of glucose into the uterine cell. In the rat uterus and in the sheep endometrium, increases in free uterine glucose were observed, but the rabbit uterus and sheep myometrium synthesized glycogen without showing an increase in free glucose in the tissue.