Figure 3.

Deletion of both Tcf7l2 alleles potentiates the effects of Lkb1 deletion on glucose tolerance and insulin secretion in males. Oral glucose tolerance experiments were performed as described in Fig. 2 legend (A and B) (n = 7–11 mice/genotype). Insulin plasma levels were measured in vivo 2.5, 5, and 15 min after intraperitoneal injection of glucose (3 g/kg) (C and D) (n = 7–8 mice/genotype). E, insulin secretion in vitro was measured from groups of 10 size-matched isolated islets during static incubation (see “Experimental procedures”) and at the indicated glucose or KCl concentrations (n = 4–6 mice/genotype; *, p < 0.05; **, p < 0.01; ****, p < 0.0001). Gray open circles, βLkb1-KO-Tcf7l2-het; black filled circles, βLkb1-Tcf7l2-dKO. Error bars represent the mean ±S.E. AUC, area under the curve.