AUTONOMIC COMPETITION IN PANCREATIC VACUOLIZATION

¹ Department of Pharmacology and Toxicology, School of Medicine, University of Southern California, Los Angeles 7, California

The vacuolizing effect of acetylcholine upon the zymogen secreting cells of the pancreas is probably through an action upon Langley's receptive substance rather than on autonomic ganglia because of the following observations: 1. Not only acetylcholine, but also arecoline, methacholine and carbachol cause the appearance of vacuoles in the exocrine cells of the pancreas. 2. The vacuolizing effects of acetylcholine are antagonized by atropine, scopolamine and Syntropan, as well as by epinephrine, ephedrine, phenylephrine and Paredrine. 3. The vacuolizing effects of arecoline, methacholine and carbachol were abolished by atropine. 4. Nicotine neither caused vacuole formation nor antagonized the action of acetylcholine. Other observations of interest in this investigation were: 5. Physostigmine salicylate and neostigmine bromide did not produce pancreatic vacuoles in the dose range employed. 6. The vacuoles produced in the exocrine pancreas by acetylcholine did not contain glycogen.

I wish to express my gratitude to Professor Clinton H. Thienes for making this project possible and for revising the manuscript. I wish, also, to thank Mr. Oliver Warren for preparing most of the microscopic material and Miss Grace Mascher for typing the manuscript. The following companies made generous gifts of drugs: nicotine tartrate, Burroughs-Wellcome Company; Neosynephrine hydrochloride, Frederick Stearns and Company; Paredrine hydrobromide, Smith, Kline, and French Laboratories; and neostigmine bromide (Prostigmin bromide) and Syntropan, Hoffman-La Roche Company through the kindness of Dr. Elmer L. Sevringhaus.