Simultaneous mechanisms on exocrine pancreatic secretion initiated by alcohol in the conscious dog

Abstract

Modifications of pancreatic secretion induced by the infusion of alcohol were investigated in seven Thomas fistula dogs. Acute intravenous injections of low doses of alcohol induced a significant increase of all parameters of pancreatic secretion. On the contrary the acute intravenous injection of high doses of alcohol induced a significant decrease of pancreatic secretion. A prolonged-alcohol intravenous infusion producing a stable blood alcohol level provoked at first a decrease of pancreatic secretion, significant only for protein output, followed by a significant increase of all parameters of pancreatic secretion. A spontaneous return to prealcohol values of pancreatic secretion was observed in all cases even if the blood alcohol level remained high and stable and despite four hours of experimentation. Upon the background of a stable blood alcohol level, pentolinium did not suppress alcohol-induced stimulation of water and bicarbonate outputs but did abolish the postalcohol changes in protein secretion. Furthermore, atropine abolished all postalcohol changes in pancreatic secretion. Consequently, there are two responses (inhibition and stimulation) to alcohol which coexist in normal dogs. They are related to the blood alcohol levels and are transitory. These responses involve the vagus nerves. Alcohol appears to stimulate the exocrine pancreas through receptors at different levels of the nervous system.

Effect of Acute and Chronic Oral Administration of Ethanol on Canine Exocrine Pancreatic Secretion

“…It had already been shown that the vagally mediated inhibition due to intravenous alcohol injection disap peared in chronic alcoholic dogs and was reversed to a strong stimulation of protein and to a lesser extent of water and bicarbon ate secretion [6], This can be explained in the light of recent experiments [22]: in nonalco holic dogs, intravenous ethanol is responsible for two opposite mechanisms, namely inhibi tion and stimulation of pancreatic secretion. Both are abolished by atropine, ganglion blockers and vagotomy, but stimulation is sensitive to much lower alcohol blood levels than inhibition.…”

Alcohol and Pancreatitis

“…Under these conditions, there remains a muscarinic stim ulatory mechanism which is localized in the intrapancreatic deuteroneuronc of the vagus or in the acinar cell itself. This could lead to an increased release of acetylcholine in the pancreas responsible for an increased (pro tein) secretion [22], …”

Changes of Duodenal pH and Pancreatic Exocrine Function after Upper G-I Intraluminal Ethanol Administration.

“…There are also contrasting reports that pancreatic exocrine secretion is suppressed (Dreiling et al 1952;Tiscornia et al 1973), and stimulated (Walton et al 1962) by intravenous administration of ethanol. Noel-Jorand and Sarles (1983) reported that suppressive and stimulative effects exist in accordance with high and low blood ethanol concentration.However, there appeared to be no reports of studies that have continuously measured variations of the duodenal luminal pH in response to gastrointestinal administration of ethanol. In our study, we simultaneously measured duodenal lumen pH and pancreatic exocrine secretion to determine the effects of gastrointes-…”

“…There are also contrasting reports that pancreatic exocrine secretion is suppressed (Dreiling et al 1952;Tiscornia et al 1973), and stimulated (Walton et al 1962) by intravenous administration of ethanol. Noel-Jorand and Sarles (1983) reported that suppressive and stimulative effects exist in accordance with high and low blood ethanol concentration.…”