Triacylglycerols in the rat uterine epithelium during the oestrous cycle and early pregnancy

Abstract

Specific histochemical techniques showed triacylglycerols to be the predominant neutral lipid in intracellular lipid droplets of uterine epithelial cells. After their extraction from pure samples of uterine epithelial cells, triacylglycerols were in lower concentration (.mu.g/.mu.g DNA) during proestrus (0.4) than at any other stage of the estrous cycle (0.73-0.86), decreased during days 3(0.5), 4 (0.25) and 5 (0.24) of pregnancy, and were lower in ovariectomized females receiving estradiol (0.18) than in those receiving medroxyprogesterone acetate (0.93). These triacyglycerols apparently could be used by the blastocysts and their contiguous endometrium as a readily available energy and metabolite source during implantation.