Effect of prostaglandin and dietary fats on lipolysis and esterification in rat adipose tissue in vitro

Abstract

1. 1. A possible role of prostaglandin (PGE 1) in lipid metabolism was investigated. It was found to inhibit the release of free fatty acids and glycerol from adipose tissue of fat-fed rats, the amount depending upon the nature of the fat ingested. The release of less glycerol and free fatty acids from tissue of rats fed a polyunsaturated fat (corn oil), as compared to those fed lard, was in effect similar to that in the presence of prostanlandin. 2. 2. Preincubation of tissue with prostaglandin produced a similar response suggesting that prostaglandin may have entered the adipose tissue cells during preincubation causing an inhibition of lipolysis. There was also a greater incorporation of [1- 14C]palmitic acid into the lipids and triglycerides of this tissue in the corn oil-fed rat and in prostaglandin-treated tissues. 3. 3. An inhibition of lipolysis and increased rate of removal of fatty acids from the medium by adipose tissue in the presence of prostaglandin or by this tissue of corn oil-fed rats, both associated with an increased esterification of fatty acids in the tissue, suggests the possibility that the effect of the latter may be the promotion of the formation by these rats of greater amounts of prostaglandin from the unsaturated fatty acids ingested.