Figure 6.

VIP receptor expression in acinar cells and their activation through PKA. (a) The levels of VPAC1 receptor mRNA expression were determined in total RNA extracted from isolated acinar cells of both strains of mice as described in Material and methods. (b) Cells were incubated in the presence or absence of 100 nM vasoactive intestinal peptide (VIP) for 15 minutes for amylase secretion assays and cAMP accumulation. cAMP was determined by radioimmunoassay and amylase by means of an enzymatic assay as described in Material and methods. *P < 0.05 vs. basal. (c) Bax mRNA expression levels were determined after TNF-α (20 ng/ml) incubation as in Figure 2 in the presence or absence of 100 nM VIP and pre-incubated or not with 1 μM H-89 (15 minutes). The intensity of the bands for Bax relative to GAPDH was measured as in Figure 5 and expressed as means ± standard error of the mean for at least three experiments run independently with non obese diabetic (NOD) (n = 12) and BALB/c (n = 10) samples. *P < 0.05 vs. TNF+VIP.