Fig. 4.

Effects of GLP-1 on beta cell lines treated with insulin/IGF-1 receptor antagonist. Western blotting for total and p-Akt, total and p-insulin receptors (IR) and IGF-1 receptors (IGF1R) in beta cells from insulin-receptor-floxed control mice. The cells were stimulated with or without 10 nmol/l GLP-1 or 100 nmol/l insulin for (a) 15 min or (b) 24 h in the presence or absence of 200 nmol/l OSI-906. Histograms show relative phosphorylation of Akt, normalised by total Akt, in control beta cells in the absence or presence of OSI-906, after treatment with GLP-1 (a) or Ex-4 (b). All data are expressed as mean ± SEM. n=3 in each group. *p<0.05 as indicated