Carbamylcholine stimulation of protein secretion in pancreatic acinar carcinoma of rat.
Pancreatic acinar carcinoma fragments, pulse-chase labeled with [3H]-leucine, responded to carbamylcholine chloride by increased secretion of [3H]leucine-labeled protein into external buffer medium. Secretion of labeled protein by the carcinoma fragments increased in concentration-dependent fashion between 10(-8) -10(-5) M carbamylcholine, was completely inhibited at 4 degrees C, and was accompanied by an equivalent increase in the secretion of preformed amylase. A maximally effective carbamylcholine concentration of 10(-5) M was observed for both carcinoma fragments and normal pancreas lobules. However, the maximal rate of protein secretion by the carcinoma fragments was only approximately one-fifth the rate determined for the normal pancreas lobules. This modest secretory response indicates a population of partially differentiated cells in the pancreatic acinar carcinoma which secrete less enzyme than fully differentiated adult pancreatic acinar cells. Secretory responsiveness can be utilized as a quantitative acinar cell response in studies on differentiation in pancreatic carcinoma.
D000681:Amylases / Q000378:metabolism; D000818:Animals; D002217:Carbachol / Q000494:pharmacology*; D002277:Carcinoma / Q000378:metabolism*; D007930:Leucine; D008297:Male; D003012:Microbial Collagenase / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000378:metabolism*; D009374:Neoplasms, Experimental / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D014316:Tritium
D009363:Neoplasm Proteins; D014316:Tritium; D002217:Carbachol; D000681:Amylases; D003012:Microbial Collagenase; D007930:Leucine