Effects of long term intravenous administration of ethanol on rat pancreas.

Abstract

Pancreatic exocrine function and morphologic changes were investigated in groups of rats receiving solutions of ethanol by oral or intravenous route, or equicaloric doses of glucose solution by intravenous route daily for a period of 4 weeks. Comparable degrees of exocrine dysfunction and morphologic changes in the pancreas at the ultrastructural level were observed in the groups given ethanol orally and in those receiving i.v. injections of ethanol, suggesting that neither intragastric ingestion nor high blood levels of alcohol is required for alcohol to exert its pancreatotoxic effects. All groups of rats receiving ethanol or glucose showed signs and pathologic findings of nutritional disorder, and at 4 weeks of treatment, electron microscopic abnormalities of the pancreas were more pronounced and higher in incidence in the groups given ethanol p.o. or i.v. than in the groups given i.v. doses of glucose. There was no microscopic evidence of protein plug or other changes in the region of origin of the pancreatic duct system in rats after 18 months of oral administration of ethanol. The present findings indicate that the cytotoxic effect of alcohol on acinar cells and nutritional disorder associated with alcohol ingestion constitute important factors in the pathogenesis of chronic alcoholic pancreatitis. chronic pancreatitis; pancreatic exocrine function; intravenous administration of ethanol; protein plug As to the mechanism by which chronic alcoholic pancreatitis develops, various theories have been proposed such as hypersecretion-obstruction theory (Dreiling 1952), the theory of protein plug (Sarles et al. 1971;Sarles 1974) and the theory of cytotoxicity (Darle et al. 1970). As to the effect of alcohol on exocrine functions of the pancreas, it has been reported that orally ingested alcohol stimulates the pancreatic secretion secondary to the increase in the gastric acid secretion, while the alcohol transferred into the blood suppresses pancreatic secretion (Woodward et al. 1957;Tiscornia et al. 1972).The present study was performed to elucidate the effects of long term intravenous administration of alcohol on the pancreas. For this purpose, using rats divided into three groups receiving alcohol either orally or intravenously, or glucose of isocalory to alcohol intravenously, the exocrine functions and morphologic changes of the pancreas were investigated.