Peripheral and Central Chemical Control of Pulmonary Ventilation.

Until the recent work of Heymans there has been little evidence for reflex chemical control of pulmonary ventilation. The demonstration of increased respiratory movements from perfusion of the carotid sinus with carbonated and deoxygenated blood calls for a study of the relative values of peripheral and central chemical control.1 Several procedures were used.The effects of injection of sodium cyanide, sodium sulphide, sodium carbonate and sodium bicarbonate into the carotid arteries after occlusion of the vertebral and external carotid arteries and denervation of one carotid sinus were noted. Injection of sodium cyanide on the side on which the innervation of the carotid sinus was intact invariably produced increased ventilation. Injection on the denervated side produced relatively small or no increase in ventilation followed by depression. In general the effects of intraarterial injection of sodium sulphide were similar to those produced by cyanide. Painting the innervated sinus with sodium cyanide or su...