[Electrophysiological evaluation of the intensity of protective respiratory reflexes]

The impulse activity of bulbar respiratory neurons and the electrical activity of main respiratory muscles were studied stereotaxically and electromyographically on 21 male and female cats anesthetized with pentobarbital (40 mg/kg, i.p.) during defensive respiratory (expiratory and coughing) reflexes. During stimulation of laryngopharyngeal and tracheobronchial receptors, a pronounced focus of excitation appears in the bulbar respiratory centre, its peripheral manifestation being powerful electrical activity of expiratory muscles (expiratory reflex) or of both expiratory and inspiratory muscles (coughing). Respiratory defensive reflexes are very powerful and stable and are retained in hypercapnia and hypoxia.