Tuncer, M1984-01-012009-06-011984-01-012009-06-011984-01-01Tuncer M. The reversal by metoclopramide of apomorphine-induced inhibition of responses to stimulation of the cardioaccelerator nerves in the cat. Indian Journal of Physiology and Pharmacology. 1984 Jan-Mar; 28(1): 15-20http://imsear.searo.who.int/handle/123456789/108911The effect of metoclopramide on presynaptic dopamine receptors was investigated in the cat cardioaccelerator nerve preparation. Metoclopramide, a substituted benzamide derivative, antagonized inhibitory action of apomorphine on positive chronotropic responses induced by sympathetic nerve stimulation in cat hearts, in vivo. Neither phentolamine, an alpha-adrenergic blocking agent, nor indomethacin a prostaglandin synthesis inhibitor, antagonized the effect of apomorphine. Apomorphine did not alter the positive chronotropic effects of intravenously administered noradrenaline. Metoclopramide potentiated stimulation-induced positive chronotropic responses. These results suggest that metoclopramide blocks the presynaptic dopamine receptors at the cat heart.engAnimalsApomorphine --antagonists & inhibitorsCatsElectric StimulationFemaleHeart --innervationHeart Rate --drug effectsIndomethacin --pharmacologyMaleMetoclopramide --pharmacologyNorepinephrine --pharmacologyPhentolamine --pharmacologyReceptors, Dopamine --drug effectsSympathetic Nervous System --drug effectsJournal Article