Some Effects of Serotonin in Pentobarbital Anesthetized Dogs

Abstract

Serotonin creatlnine sulfate given by rapid pulmonary arterial injections into pentobarbital-anesthetized dogs always produced purely pressor responses in both pulmonary and systemic circuits. Bradycardia, ecg. disturbances, bronchoconstriction, and hyperpnea followed by apnea occurred in the majority of the experiments. Increases in pulmonary and systemic vascular resistances were quickly followed by a rise in cardiac output which helped maintain the pressor response to serotonin. The close coincidence in the onset of the vascular and respiratory effects suggested neural participation in the production of these responses.