[Endogenous opioids in respiratory inhibition by laryngeal stimulation]

The reflex effect elicited by mechanical stimulation of the glottis has been studied in dogs. The three components of the response--sudden apnea, constriction of the glottis and bradycardia--were modified by naloxone, although not in the same degree. These results suggest the existence of opioid interneurons between laryngeal afferent fibers and central inspiratory neurons.