Triacylglycerols and glycerophospholipids in ovaries from maturing and superovulated immature rats.
The concentration and composition of triacylglycerols and glycerophospholipids in the rat ovary were measured during the development of follicles to corpora lutea. Changes occurring during normal development, as the rats aged from 20 to 41 days, were compared with those following treatment of 20-day-old rats with gonadotrophin to stimulate superovulation. In the ovaries of immature superovulated rats, where many follicles developed into corpora lutea in synchrony, the glycerophospholipids increased in concentration throughout growth and luteinization. At the same time the total amount of triacylglycerol rose 10-fold but only increased in concentration during the 24 h after administration of pregnant mare's serum gonadotrophin. In both classes of lipid the proportion of polyunsaturated fatty acids rose throughout. Six days after administration of gonadotrophin 20% of the fatty acid in glycerophospholipid was arachidonic acid (20:4), while the amount of 22:5 acid had risen from 3 to 17% in the triacylglycerols. During normal aging, changes in the developing follicles were masked by the number of other cell types present. In the whole ovary the glycerophospholipids did not change between 20 and 41 days, but the triacylglycerol concentration rose. However, there was a marked similarity between the concentrations of both lipid classes in corpora lutea dissected out of the 41-day-old ovary and those of the superovulated rats. The changes in proportion of the polyunsaturated fatty acids were also the same during normal and stimulated development of the corpora lutea. In the day-41 corpus luteum the phospholipid contained 22% arachidonic acid (20:4), and 20% of the fatty acids in the triacylglycerol was 22:5. The changes in composition of fatty acids suggests that when a follicle begins to develop there is transfer of polyunsaturated fatty acids from cholesterol esters in the interstitial tissue to the triacylglycerols.
D000818:Animals; D003338:Corpus Luteum / Q000254:growth & development; D005227:Fatty Acids / Q000378:metabolism; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology; D010053:Ovary / Q000254:growth & development* / Q000378:metabolism; D010060:Ovulation / Q000187:drug effects; D010712:Phosphatidic Acids / Q000378:metabolism*; D051381:Rats; D013480:Superovulation / Q000187:drug effects; D014280:Triglycerides / Q000378:metabolism*
D005227:Fatty Acids; D006064:Gonadotropins, Equine; D010712:Phosphatidic Acids; D014280:Triglycerides