Secretory capacity of isolated pancreatic acinar cells.

Abstract

Summary: In order to characterize the secretory capacity of isolated acinar cells, the effects of various secretagogues on amylase release were studied in guinea pigs. The effect of carbachol on amylase secretion reached a maximal level after a 30-min incubation and was dose dependent. At 10 −4 M, carbachol induced a 33% increase in amylase secretion over control values (P < 0.001); at 10−6 M, there was an 8% increase over control (P < 0.05); and, at 10 −8 M, there was no change in amylase secretion. Muscarinic blockade with equimolar concentrations of atropine completely blocked the expected carbachol-induced increase in amylase secretion after both 30− and 60-min incubations. The response to secretin was neither significantly different from that to carbachol nor dose dependent over the concentration range tested. After a 30-min incubation, secretin induced significant increases in amylase secretion of 23%, 19%, and 23% at concentrations of 10 −5 M, 10−7 M, and 10−9 M, respectively. As with carbachol, the response to secretin was blocked by atropine. Secretion of amylase in response to cholecystokinin-pancreozymin octapeptide (CCK-PZ) was maximal after a 30-min incubation and was dose dependent. CCK-PZ, at concentrations of 10−7 M and 10−9 M, induced significant increases in amylase secretion of 18% (P < 0.001) and 17% (P < 0.001), respectively. At 1011 M, CCK-PZ did not evoke a significant increase in amylase secretion. The CCK-PZ-induced increase in amylase secretion was significantly less than that observed with carbachol (P < 0.05), was not significantly different from that observed with secretin, and was not potentiated by the simultaneous exposure of the acinar cells to carbachol.