Meal-feeding specifically induces obese mRNA expression

Meal-feeding caused a rapid and specific induction of ob mRNA levels in rat adipose tissue. A high-carbohydrate meal caused a mean 5-fold increase in ob mRNA within 3 h after feeding and almost reached the levels of expression seen in rats fed ad lib. After the meal ob mRNA declined with a half-life of less than 2 h. The increase in ob mRNA in response to the meal was prevented by prior injection of actinomycin-D, an inhibitor of transcription. None of the mRNAs for other genes involved in lipid metabolism (lipoprotein lipase, fatty acid synthase, malic enzyme, hormone-sensitive lipase, S14 or adipsin) showed any significant difference between pre-meal and post-meal levels. (C) 1996 Academic Press, Inc.