Increase in weight of the submandibular salivary glands of rats following periodic amputation of the erupted portion of the incisor teeth

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

Periodic amputation of the erupted portion of the lower incisors of albino rats resulted in a marked increase in the wet and dry weight of the submandibular salivary glands as early as 7 days after the first amputation. Enlargement of both serous and mucous acini was observed, but no effect on the cells of the tubules could be detected. Amputation of the upper incisors alone did not result in enlargement of the submandibular glands. Hypophysectomy decreased the extent of the response to amputation of the lower incisors but did not abolish it. Chronic treatment with cortisone had no significant effect on the weight of the glands. A reflex neurologic explanation was offered as a tentative basis for understanding the phenomenon and as a starting point for further investigation.