Figure 1: ILK in pancreatic islets is required for a normal localization of their vasculature.

(a) Blood glucose concentrations during a glucose tolerance test in male ILK cKO mice (filled squares) and heterozygous littermate controls (unfilled squares) at the age of 7 weeks. Glucose (1 g kg⁻¹ body weight) was injected i.p. at 0 min. N=7–8 mice per experimental group. (b) Area under curve of data shown in a. (c) Plasma insulin concentrations in male ILK cKO and control mice (10-weeks-old). Glucose (1 g kg⁻¹ body weight) was injected i.p. at 0 min. N=8 mice per experimental group for 0 and 30 min (left panel), and N=3–4 mice per group for 0 and 120 min (right panel). (d) Insulin secretion from isolated pancreatic islets of ILK cKO and control mice at 2.5 mM (white dots) or 20 mM (black dots) glucose. Secreted insulin is normalized to total insulin levels. N=3–4 islet batches each. (e) Laser scanning microscopy (LSM) images of immunofluorescence staining for insulin (a marker for pancreatic beta cells) and CD31 (a marker for blood vessels) of pancreatic sections from 12-weeks-old control and ILK cKO mice. Quantification of intra-islet, peri-islet and total islet blood vessel densities in ILK cKO and control mice. N=3 animals per experimental group, 8–10 islets were analysed per animal. (f) LSM images of immunofluorescence staining for insulin and CD31 in pancreatic sections from 1 day (P1), 7 days (P7) and 14 days (P14) old control and ILK cKO mice. (g–i) Quantification of (g) the intra-islet vascular density, (h) the peri-islet vascular density and (i) the total islet vascular density, each relative to the insulin⁺ pancreatic beta cell number. N=3 animals per experimental group with 28–39 (P1), 53–114 (P7) and 47–77 (P14) islets analysed per animal. Data are shown as mean values±s.d., *P<0.05 in an unpaired, two-sided Student’s t-test with (a) Holm-Bonferroni correction. Scale bars, 50 μm (e,f).