Amylase Release from Pancreatic Slices of Rat Treated with Adrenergic Drugs

아드레나린성 약물 전처치 흰쥐의 취절편 효소분비에 관한 실험

The exocrine pancreatic secretion is controlled mainly by gastrointestinal hormones as well as cholinergic nerves. The adrenergic influence on exocrine pancreas is thought not to he important and the evidences supporting this contention are still contradictory. In an effort to elucidate the adrenergic influence on the exocrine pancreas, we have determined the amylase release from pancreatic slices of rats treated with adrenergic drugs. The albino rats of either sex, weighing $60{\sim}80\;g$, were decapitated and the uncinate pancreata were isolated and incubated in screw top vials containing 2 ml krebs-Ringer bicarbonate buffer solution gassed with 95% $O_2$ and 5% $CO_2$. These vials were shaken continuously in a waterbath maintained at $37^{circ}C$, and enzyme release was stimulated with acetylcholine$(10^{-5}M)$. For chronic treatment methoxamine$(an\;{\alpha}-adrenergic\;agonist,\;5\;mg/kg)$, isoproterenol (a\;{\beta}-adrenergic\;agonist,\;10\;mg/kg) and reserpine (0.5 mg/kg) along with cholecystokinin octapeptide$(CCK-op,\;2{\mu}g/kg)$ were given i.p. in rats daily for 3, 5, 7, 9 or 12 days. For acute experiment these drugs were added directly to the incubation medium in a concentration of $10^{-5}M$ except CCK-OP $(10^{-9}M)$. The results are summarized as follows. 1) The addition of methoxamine, isoproterenol or reserpine to the incubation medium containing pancreatic slices augmented the release of amylase induced by acetylcholine and among them the effect of isoproterenol was most prominent. 2) Chronic treatment of methoxamine or reserpine caused enhancement of acetylcholine response in amylase release from pancreatic slice throughout the experimental period, but the amylase release was less than that of control by 12 days isoproterenol treatment. 3) In the pancreatic slices obtained from 12 days treatment of CCK-OP, the amylae release responding to acetylcholine was enhanced. By these finding it is suggested that methoxamine, isoproterenol and reserpine had marked influence on the exocrine pancreatic functions in rats and that these effects are due to their inherent actions rather than sympathetic nerve or adrenergic receptor function.