Acute changes in ventilation and blood pressure induced by inhalation of tobacco smoke.

Inhalation of cigarette smoke through a tracheal cannula was induced in cats anesthetized with pentobarbital. Smoking of tobacco cigarettes produced increased ventilation and systemic hypertension, which were found to be due to their nicotine content. Respiratory stimulation and the increase in diastolic pressure were abolished by acute section of 'buffer nerves', but the mediation of carotid nerves was more important than that of the vagi for evoking reflex hyperventilation. Tobacco smoking induced a marked increase in the frequency of chemosensory impulses recorded from the carotid nerves, an effect due to its nicotine content.