Cholinergic receptor induction and JNK activation in acute pancreatitis

BACKGROUND: Cholecystokinin-A (CCK-A) and cholinergic receptor pathways, capable of activating stress kinases p38 mitogen-activated protein kinase (p38(MAPK)) and cJUN N-terminal kinase (JNK), are implicated in the pathogenesis of ligation-induced acute pancreatitis in rats. As ligation-induced acute pancreatitis in rats is associated with CCK-A receptor induction and p38(MAPK) activation, and as receptor induction could amplify acinar hyperstimulation and exacerbate cell stress, we tested the hypothesis that the cholinergic M3 receptor is induced and JNK is activated in this model. METHODS: Cholinergic M3 receptor expression and JNK activation was compared in rats 1, 3, or 24 hours after sham operation or duct ligation. RESULTS: Immunoblot analysis of pancreatic homogenates showed a time-dependent increase in cholinergic M3 receptor protein, total JNK, and phospho-JNK after duct ligation. CONCLUSIONS: There is a rapid and progressive cholinergic M3 receptor induction and JNK activation in ligation-induced acute pancreatitis in rats. These findings may have significance in the mechanism of disease pathogenesis.