Figure 3.

Liver gene expression in adult WT mice and mice homozygous for a deletion of the C/EBPβ gene (–/–). (a) Ten-week-old female C/EBPβ^–/– and WT mice were fasted overnight before being anesthetized and sacrificed, and the total liver RNA was isolated. The RNA was subjected to Northern blot analysis, and the blot was hybridized sequentially with probes for PEPCK, G6Pase, and glucokinase. Results were normalized to the level of actin mRNA and expressed relative to WT controls. (b) Effect of Bt₂cAMP on the expression of genes for PEPCK, G6Pase, and glucokinase. Mice were fed a high-carbohydrate diet (81% sucrose) for 5 days, followed by intraperitoneal injection with 60 mg Bt₂cAMP/kg of body weight and 25 μg of theophylline in 150 μl of saline, and were sacrificed 2 h later (27). The livers were frozen at –80°C until they were analyzed. RNA was isolated and Northern blot analysis carried out as described in a. The bars represent the mean ± SEM of four to six animals per group. PEPCK, phosphoenolpyruvate carboxykinase; G6Pase, glucose-6-phosphatase; Bt₂, N⁶,O²′-dibutyryladenosine.