Effects of prostaglandins on the metabolism of cholesteryl ester in rat testes: changes in the synthesis and hydrolysis of cholesteryl ester and the activity of cholesterol side-chain cleavage enzyme.

The effects of prostaglandins on testicular synthesis and hydrolysis of cholesteryl esters, the activity of the enzyme involved in cleavage of the cholesterol side-chain and on serum levels of testosterone and LH have been studied. Subcutaneous administration of prostaglandins to male rats caused an increase in the concentration of cholesteryl esters in the testes, a decrease in testicular synthesis and hydrolysis of cholesteryl esters but no change in the activity of the cholesterol side-chain cleavage enzyme. There was also a significant decrease in the serum level of testosterone, but the level of LH was raised. Prostaglandins also affected the fatty acid composition of lipids in rat testicular tissue; cholesteryl esters were found to contain greater amounts of arachidonic (C20:4) and docosapentaenoic (C22:5) acids. These findings suggest that prostaglandins are involved in the turnover of cholesteryl esters in rat testicular tissue and regulate the production of androgens.