Antiketonemic effect of glycerol during development of the rat

Glycerol, which decreased circulating levels of ketone bodies in adults, was tested for its antiketonemic action in developing rats. Following intraperitoneal injection of glycerol in rats from 2 to 90 days of age, blood levels of 3-hydroxybutyrate (beta HOB) decreased and reached minimum values in 35-40 minutes. The pattern of recovery in suckling animals (2, 7 and 14 days of age) differed from that of 24-, 35- and 90-day-old rats. Glycerol did not change blood acetoacetate (Ac2) levels in suckling rats but caused marked reductions in fasted older animals. The effect of glycerol on the ration of beta HOB:Ac2 was strikingly different for 90-day-old rats compared to all other groups. Glycerol did not raise blood glucose levels in neonatal or suckling rats. These developmental patterns of response to glycerol differed remarkedly from those to alanine, suggesting differential antiketonemic mechanisms for these two compounds on in vitro rats of beta HOB synthesis in liver homogenates from rats injected with either glycerol or alanine.