Liver lipogenesis in vivo in fed and food deprived suckling rats

Abstract

Liver Lipogenesis in vivo in Fed and Food Deprived Suckling Rats. Rev. esp. Fisiol., 30, 31-36. 1974.
Lipogenesis was examined in the liver of fed or 24 hr food deprived rats of 5, 10, 20 or 30 days of age and in adults at 10 and 30 min after administration of trace or subs­ trate concentrations of pyruvate 3-“C. In fed rats, the incorporation of radioactivity into liver lipids was inversely related to the age of the rats. Food deprivation increased the incorporation of *4C into liver lipids only in the 20 and 30 days old rats given the trace concentration of pyruvate and in the adults given the substrate concentration. Practically all the radioactivity incorporated into lipids in the fed and food deprived suckling rats entered the glyceride glycerol fraction. This suggests that lipogenesis is negligible in suckling rats. The incorporation of radioactivity into the glyceride glyc­ erol fraction was low in the 30 days old rats and adults. It increased afted food depri­ vation. This suggests that lipogenesis is inhibited by food deprivation in the older rats. The findings are discussed in terms of the balance between carbohydrate and lipid metabolism in the liver of the suckling rat.