Effects of acute intravenous ethanol on basal exocrine pancreatic secretion in rat: cholinergic involvement

The effect of intravenous infusion of ethanol on the basal exocrine pancreatic secretion of anesthetized rats was studied. The cholinergic involvement on the actions of ethanol was also studied using previously atropinized animals. During the stimulation period, pancreatic flow rate was significantly increased by intravenous ethanol in both un-atropinized (199% compared with basal) and atropinized rats (195% compared with basal). Pancreatic protein output was also increased during ethanol administration in both groups of animals (171% and 165% compared with basal in, respectively, un-atropinized and atropinized rats). After the administration of ethanol, in the poststimulation period, pancreatic flow rate was further increased only in the atropinized group of rats (290% compared with basal), whose values were significantly higher than those of ethanol-treated un-atropinized animals (195% compared with basal). A similar profile of response was observed in pancreatic protein output. Since intravenous ethanol did not stimulate either secretin or VIP release to portal plasma, the present results point to a direct effect of this substance on the exocrine pancreas. Furthermore, atropine revealed the existence of an inhibitory cholinergic effect of ethanol on the exocrine pancreas. In summary, results show that the effect of intravenous ethanol on the basal exocrine pancreatic secretion is dual and antagonistic.