Pancreatic Alpha-Cell Dysfunction Contributes to the Disruption of Glucose Homeostasis and Compensatory Insulin Hypersecretion in Glucocorticoid-Treated Rats
Figure 5
Glucagon stimulates insulin secretion in islets isolated from DEX rats.
A: Insulin secretion in response to incubation with 5.6 mmol/l glucose with or without glucagon or forskolin in islets isolated from DEX and CTL rats (n = 10 wells). B: Representative immunoblots for the glucagon receptor (GR) and β-actin and their quantification (bar graphs) for DEX and CTL islet lysates (n = 6 independent samples). Data are the mean ± SEM. * p<0.05, *** p<0.001 vs. CTL. ††† p<0.001 vs. 5.6 m glucose. ‡‡‡ p<0.001 vs. 5.6 mmol/l glucose plus 1 µmol/l glucagon in A. C: Immunostaining of pancreas sections from DEX and CTL rats for the GR (green) and insulin or glucagon (red). Merged in orange. DAPI was used for nuclei staining (n = 3 pancreases). Scale bars = 7.5 µm.