EXOGENOUS ADMINISTRATION OF ESTRADIOL AND CHOLECYSTOKININ ALTERS EXOCRINE PANCREATIC FUNCTION IN RATS

This study was conducted in rats to investigate the influence of exoge nously administered estradiol (ESD) and/or cholecystokinin (CCK) on co mponents and secretions of the pancreatic acini. Intact male rats were treated for 14 d with exogenous administration of ESD, CCK, or ESD CCK. After 14 d CCK treatment induced significant increases in DNA and RNA contents, and DNA/RNA ratio in the pancreas, indicating hyperplas ia and hypertrophy of the pancreas, however, ESD treatment did not hav e these effects. Both ESD treatment and CCK treatment induced signific ant increases in amylase and trypsinogen contents in pancreatic acini and each decreased secretion from acini in response to CCK. Combined t reatment with ESD plus CCK augmented these effects on enzyme contents and secretion. The results indicate that exogenous administration of C CK has trophic effects on the exocrine pancreas, increasing effects on enzyme contents and inhibitory effects on amylase secretion. In contr ast, exogenous administration of ESD had no trophic effects on pancrea s, but had increasing effects on enzyme contents and inhibitory effect s on amylase secretion. The results suggest that the effects of exogen ous ESD and CCK on pancreas are not similar to each other, but both ES D and CCK may be involved in regulating pancreatic exocrine functions.