Ethanol-induced alterations in messenger RNA levels correlate with glandular content of pancreatic enzymes.

Ethanol abuse is a well-known association of pancreatitis. The effects of chronic ethanol consumption on pancreatic digestive and lysosomal enzymes may be relevant to the pathogenesis of alcoholic pancreatitis, because pancreatic enzymes play an important role in the development of pancreatic injury. The aims of this study were to determine the effects of ethanol on gene expression and glandular content of pancreatic digestive enzymes and on gene expression of the lysosomal enzyme cathepsin B (known to be capable of activating trypsinogen). Pancreatic content and mRNA levels for lipase, trypsinogen, and chymotrypsinogen were determined in rats that were pair-fed a nutritionally adequate liquid diet with or without ethanol for 4 weeks. mRNA levels for the lysosomal enzyme cathepsin B were also assessed in this model. Ethanol significantly increased the content of lipase in the pancreas. There was a trend toward an increase in trypsinogen and chymotrypsinogen levels; however, these differences were not statistically significant. mRNA levels for lipase, trypsinogen, and chymotrypsinogen were raised in ethanol-fed rats. Ethanol feeding also increased mRNA levels for the lysosomal enzyme cathepsin B. Furthermore, there was a close, statistically significant correlation between changes in mRNA levels and tissue activities of pancreatic digestive and lysosomal enzymes after ethanol consumption. These results suggest that ethanol increases the capacity of the pancreatic acinar cell to synthesize digestive and lysosomal enzymes, thereby increasing the susceptibility of the gland to enzyme-related injury.