Submandibular salivary gland enlargement by feeding pancreatin to rats

¹ Biological Research Laboratories, Harvard School of Dental Medicine, and Department of Pharmacology, Harvard Medical School, Boston, Massachusetts

Addition of pancreatin, a dried and defatted preparation of porcine pancreas, to the diet of rats resulted in a marked increase in both the fresh and dry weights of the submandibular salivary glands. A range of pancreatin doses, from 0.25 to 4% resulted in a dose-response curve with little effect below 0.5%, a plateau above 2%, and a straight line between the 0.5 and 2% dose levels. After cessation of pancreatin administration, there was a marked recession in the weight of the enlarged glands. Prior unilateral extirpation of the superior cervical sympathetic ganglion inhibited the response to dietary pancreatin of the submandibular gland on the operated side. In contrast to its effect when ingested, pancreatin had no significant effect on gland weight when administered by stomach tube. When added to the diet at only one-tenth the dose of pancreatin, alpha-chymotrypsin (3x crystallized) had an equal effect on gland weight. Chymotrypsinogen (3x crystallized) and trypsin (2x crystallized) were without significant gland growth activity. A partially purified extract of pancreatin had almost the same relative potency as crystalline alpha-chymotrypsin.

Key Words: accelerated growth • sympathetic nerves • sialadenotrophic effect of chymotrypsin • pancreatic sialadenotrophic factor

Submitted on June 10, 1963