Figure 3.

Reciprocal changes of Insig-2a and Insig-1 in livers of mice subjected to fasting and refeeding. Wild-type mice were subjected to a fasting and refeeding protocol, and total RNA from livers of four C57BL/6J male mice (12 weeks of age) was pooled and subjected to real-time PCR quantification as described in Materials and Methods. The nonfasted group (N) was maintained on ad libitum diet, the fasted group (F) was fasted 12 h, and the refed group (R) was fasted for 12 h and then refed a high-carbohydrate/low-fat diet for 12 h before study. Each value for the fasted and refed groups represents the amount of mRNA relative to that of the nonfasted group, which is arbitrarily defined as 1. FAS, fatty acid synthase. Values for plasma glucose and plasma insulin (mean ± SE) in the three groups of mice were as follows: nonfasted, 174 ± 14 mg/dl and 1.3 ± 0.7 ng/ml; fasted, 98 ± 13 mg/dl and 0.15 ± 0.01 ng/ml; and refed, 188 ± 10 mg/dl and 11 ± 1.2 ng/ml.