title: Visualization of amylase secretion from individual pancreatic acini.
abstract: To assess the secretion of individual rat pancreatic acini, we developed a reverse hemolytic plaque assay that allows for a direct visualization of amylase release. This release was detected around secreting cells by the presence of hemolytic plaques that resulted from the complement-mediated lysis of red blood cells bearing amylase-antiamylase complexes bound to protein A. Controls showed that these plaques reflected specifically the active secretion of amylase. Quantitation of hemolytic plaques showed that after a 30-min incubation approximately 50% of the acini secreted under basal conditions. Stimulation of amylase release by increasing concentrations of carbamylcholine resulted in a dose-dependent recruitment of secreting acini as well as in a time-dependent enhancement in the response of individual acini. Under all conditions, the wide distribution of hemolytic plaque sizes indicated large differences in the secretory output of individual acini. Thus, using a new method to directly visualize and quantitate amylase secretion, we have provided evidence for a functional heterogeneity of pancreatic acini.
mesh_terms: D000681:Amylases / Q000378:metabolism*; D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D006462:Hemolytic Plaque Technique; D008297:Male; D008858:Microscopy, Phase-Contrast; D010179:Pancreas / Q000187:drug effects / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D012633:Secretin / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
chemical_list: D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D002217:Carbachol; D000681:Amylases