Hepatic Stearoyl-CoA Desaturase Activity in Mice as Affected by Early Postnatal Dietary Cyclopropene Fatty Acids

Abstract
The effect of inhibition of hepatic microsomal stearoyl-CoA desaturase in the early postnatal period by dietary cyclopropene fatty acids (CFA) on the activity of the enzyme in adult mice was investigated. Feeding 0.2% CFA in the form of Sterculia foetida seed oil to lactating mice from 1 day to 30 days postpartum inhibited the hepatic stearoyl-CoA desaturase activity of the month-old pups. CFA-free diet fed during the second month did not restore the activity of the desaturase. The Halphen reaction of the lipids of the adult mice indicates that even though the characteristic absorption at 500 nm due to CFA was absent, there was a sharp absorption at 550 nm. This absorption could be due to a residual cyclopropene-containing metabolite of CFA which may also inhibit stearoyl-CoA desaturation. sn-Glycerophosphate-acyltransferase activities were high in the CFA groups at all stages of development. The mechanism of this effect is not clear.