THE EFFECT OF BARIUM CHLORIDE ON THE SALIVARY SECRETION

¹ From the Department of Physiology, McGill University, Montreal, Canada

1. Intravenous introduction of barium chloride in doses of from 0.005 to 0.01 gram per kilogram body weight produces a secretion of saliva from the submaxillary gland in the dog and cat.

2. The effect is greater when the drug is injected after stimulation of the chorda tympani.

3. The secretion activated by barium chloride closely resembles that activated by the chorda tympani: (a) It is abolished by atropin; (b) after atropinization it may, like the chorda tympani secretion, be restored by large doses of physostigmin; (c) the composition of the saliva is very similar in both cases.

4. The contractile mechanism of the gland appears to be quite unaffected by barium chloride.

5. The secretion produced by barium chloride injections is accompanied by a diminution of the blood flow through the gland and a considerable elevation of the blood pressure. The former phenomenon also occurs in cases where there is no secretion and is therefore independent of the secretion.