Dynamic analysis of secretagogue-induced amylase secretion from rat pancreatic acini studied by perifusion system.

Abstract

A perifusion system was applied for the study on stimulusenzyme secretion coupling in dispersed pancreatic acini. The system is highly simple, preserves the acini up to more than 3 hr, and makes feasible clear-cut examination on the time course of enzyme secretion caused by secretagogues. Caerulein (10-s M) and carbamylcholine (10-5 M) caused a biphasic amylase secretory pattern consisting of an initial burst secretion and a sustained one. Caerulein induced a persistent amylase release even after cessation of the stimulation, while carbamylcholine-stimulated amylase release returned to basal levels. Atropine inhibited completely carbamylcholine-stimulated amylase release and the successive stimulation by caerulein evoked the amylase secretion with a decreased initial burst secretion. In calcium free medium, caerulein and carbamylcholine induced only a slight secretion, particularly in the sustained secretion phase and a gradual increase occurred with the addition of calcium.

The inhibitory effect of CR-1409 on amylase secretion and intracellular Ca2+ mobilization in rat pancreatic acini in vitro.

“…Thus, we observed the direct actions of secretagogues and its inhibitorr in the dispersed pancreatic acini. We could also examine the exact time course of amylase secretion induced by secretagogues and the effect of an inhibitor on dispersed acini in a perifusion system (IMAMURA et al, 1983;SHINozAKI et al, 1986).…”

“…Pancreatic acini were isolated from male Wistar King albino rats (250-300 g body weight) by digestion with collagenase and mechanical dissociation, by the method of JAMIESON (1972, 1974), with some modifications (IMAMURA et al, 1983;SHINoZAKI et al, 1986;SHINoz xI and FUNAKosHI, 1988). The rats were starved overnight and killed by cervical dislocation.…”

“…The perifusion system consisted of a peristaltic minipump, a perifusion chamber, and a fraction collector as described by IMAMURA et al (1983). Pancreatic acini were injected into the perifusion chamber equipped with a filter (5.0 pm pore size, SNMP, Millipore Corp.).…”

“…Cell viability, assessed by the trypan blue exclusion test, was not affected by the loading of fura-2/AM. Secretagogues were used at the submaximal concentrations determined previously (IMAMURA et al, 1983;SHINOZAKI et al, 1986;SHINOZAKI and FUNAKOSHI, 1988 …”

The relationship between free cytosolic calcium and amylase release in rat pancreatic acini.

“…secretion in detail, we employed a perifusion system of dispersed rat pancreatic acini as described previously by IMAMURA et al (1983) in our laboratory. Pancreatic acini placed on a filter (5 um pore size, SMWP, Millipore Corp., Bedford MA, U.S.A.) in a perifusion chamber were perifused with a medium through tubing, using a pump.…”