In 20-day pregnant rats, prostaglandin F2α increased lipoprotein lipase activity in mammary gland fourfold and decreased serum triacylglycerol by 50% compared to control.
Prostaglandin F(2alpha) regulates lipoprotein lipase activity and serum triacylglycerol in late pregnancy, likely via inhibition of progesterone secretion.
Absolute Event Rate: 791% vs 265%
p-value: p=<0.01
The effects of several prostaglandins on lipoprotein lipase activity of mammary gland and adipose tissue and serum triacylglycerol were studied during late pregnancy in rats. Prostaglandins were injected twice daily for 2 days before and once on the day of analysis. In rats pregnant 20 days, prostaglandin F(2alpha) (PGF(2alpha)) increased the activity of lipoprotein lipase in mammary gland fourfold, reduced the activity in adipose tissue about 60%, and decreased serum concentration of triacylglycerol 50%. PGF(2alpha) also reduced serum concentration of progesterone 90% and increased that of prolactin fivefold, but had no effect on serum concentrations of either immuno-reactive insulin or 17beta-estradiol. Injections of 13,14-dihydro-15-keto PGF(2alpha), a metabolite of PGF(2alpha), had similar effects in rats pregnant 20 days, whereas prostaglandins E(1) and E(2) did not. In rats pregnant 16 days, PGF(2alpha) did not affect lipoprotein lipase activity in the tissues or the concentration of triacylglycerol and prolactin in serum, although it decreased serum progesterone 80%.2-Br-alpha-ergocryptine prevented the increase in serum prolactin in response to PGF(2alpha), but did not alter the effect of PGF(2alpha) on lipoprotein lipase activity or serum triacylglycerol. Progesterone completely blocked the effects of PGF(2alpha) on lipoprotein lipase activity and serum triacylglycerol and prolactin concentrations. These findings indicate that the changes in lipoprotein lipase activity and serum triacylglycerol in PGF(2alpha)-treated rats are probably related to the inhibitory action of PGF(2alpha) on progesterone secretion. They also suggest that endogenous F prostaglandins may play a role in the regulation of lipoprotein lipase activity in mammary gland and adipose tissue near parturition.
Spooner et al. (Thu,) conducted a other in Late pregnancy. Prostaglandin F2α (PGF2α) vs. Diluent carrier solution was evaluated on Lipoprotein lipase activity in mammary gland (mU/g) in 20-day pregnant rats (p=<0.01). In 20-day pregnant rats, prostaglandin F2α increased lipoprotein lipase activity in mammary gland fourfold and decreased serum triacylglycerol by 50% compared to control.