Galanin inhibits rat pancreatic amylase release via cholinergic suppression

Abstract

The effects of galanin on pancreatic exocrine function were examined using rat pancreatic tissues. In anesthetized rats, galanin (40 [mu]g/kg/h) decreased amylase secretion stimulated by 2-deoxy glucose (5.8 +/- 0.1 vs. 3.1 +/- 0.1 times basal) and cholecystokinin octapeptide (21.5 +/- 0.6 vs. 16.8 +/- 0.5), while not inhibiting bethanechol-stimulated secretion. In dispersed acini, there was no effect of galanin alone (10-8 to 10-13 M) on amylase release, nor did galanin (10-6 or 10-8 M) coincubation affect amylase release stimulated by bethanechol (10-3 to 10-7 M) or CCK-8 (10-8 to 10-13 M). Using pancreatic lobules, coincubation with galanin (10-6 M) suppressed 75 mM KCl-stimulated amylase secretion and ACh release (10.1 +/- 0.6% vs. 7.3 +/- 0.4%). Veratridine-stimulated (10-4 M) amylase secretion and ACh release (12.4 +/- 1.7% vs. 8.5 +/- 0.7%) were similarly diminished.