Role of the chemoreceptor trigger zone in cyclopropane induced emesis in dogs

Inhalation of cyclopropane in dogs, by the closed circuit method, for a fixed period, produced an emetic response during recovery from anaesthesia. Bilateral surgical ablation of the emetic chemoreceptor trigger zone of the area postrema rendered the dogs refractory to several times (3-6) the threshold emetic dose of cyclopropane.