Glucose-6-phosphate dehydrogenase activity in adipose tissue from two types of obese mice during starvation

The activity of the enzyme glucose-6-phosphate dehydrogenase (G6PD) has been studied in congenital obese hyperglycemic (Obob) and gold thioglucose obese mice (GTO) and appropriate controls during periods of starvation. Obob mice show no fall in enzyme activity during starvation, an observation in keeping with the fact that the rate of lipogenesis remains high in these animals on starvation. GTO mice show a significant fall in enzyme activity by 24 hours of fasting, the level remaining low thereafter. After an initial fall in enzyme activity at 12 hours, normal Ob control and DBA 2 J mice show an apparent rise in enzyme activity at 24 hours followed by a secondary fall, and it is theorized that this rise in activity may represent a gluconeogenetic adaptive mechanism to starvation.