REGULATION OF RESPIRATION.—THE EFFECT UPON SALIVARY SECRETION OF THE INTRAVENOUS ADMINISTRATION OF AMMONIUM CHLORIDE AND AMMONIUM CARBONATE

¹ Department of Physiology of the University of MIichigan, and the Department of Physiology and Pharmacology of the University of Alberta

When the submaxillary gland of the dog is made to secrete at a constant rate by continuous intravenous injection of pilocarpine after cutting the chorda tympani supplying the gland, the administration of ammonium chloride and of ammonium carbonate produces an initial increase and a subsequent decrease in the rate of secretion. With both agents the initial increase is more marked, and with ammonium carbonate the subsequent decrease is greater if the vago-sympathetic is also cut before the injection.

Both ammonium chloride and ammonium carbonate increase submaxillary blood-volume flow. With the former the increase is greater with the vago-sympathetic intact; with the latter it is greater with the nerve cut.

Both substances in a dose of 1 c.c. per kilogram of M/6 solution produce a transient fall in blood-pressure and a brief increase in pulmonary ventilation. Ammonium carbonate in a dose of 5 c.c. per kilogram lowers the blood-pressure and depresses pulmonary ventilation, both for a short period only.

It is believed that changes in blood-volume flow and in acid base equilibrium are factors in the production of the effects upon salivary secretion of ammonium chloride and ammonium carbonate. Since ammonium carbonate may turn the tissues alkaline, an additional and stronger action of the ammonium ion seenms indicated. Further, the possibility of modification of the results by the rate of penetration of the ions into the cells is discussed.

I am greatly indebted to Professor Robert Gesell, who cordially afforded me the privileges of his laboratory for the carrying out of the experiments upon which this series of papers is based. His interest and advice have been of great assistance throughout.