Effect of the linoleic acid concentration of mother's diet on adenyl cyclase activity of fetal and neonatal rat brown adipose tissue.

An adenyl cyclase activity was measurable in the brown adipose tissue of fetal rat, and could be stimulated in vitro by noradrenaline during the last 3 days of fetal life. The stimulating effect of noradrenaline was maximal at birth and decreased during the first days of extrauterine life. Ingestion by mother of a high lipid diet modified the developmental pattern of fetal adenyl cyclase. The linoleic acid content of mother's diet had no effect on the noradrenaline- or fluoride-stimulated specific activities except on the day 22 of gestation. Relative noradrenaline-stimulated activity, expressed as a fraction of the maximal activity, was significantly increased in fetuses and 1-day-old newborns from mothers fed a high linoleic acid diet, but no effect was observed in suckling newborns.