Figure 4.

NIK Activation in Islet β Cells Inhibits Glucose-Stimulated Insulin Secretion

(A and B) Islets were isolated from male β-NIK-OE and control mice (8 weeks of age) and treated with low (2.8 mM) glucose for 1 h and then high (16.7 mM) glucose for 1 h. Insulin secretion (A) and islet insulin content (B) were measured by ELISA (β-NIK-OE: n = 5; control: n = 5). (C) The expression of genes related to insulin secretion (Gck, Glut2, Hnf1α, Hnf1β, Hnf4α, Insulin1/2, Neurod1, and Pdx-1) was measured by qRT-PCR (β-NIK-OE: n = 7; control: n = 7). ∗p < 0.05, ∗∗p < 0.01. Data represent the mean ± SEM.