Evidence that the action of clonixin is non-dependent of ACh release

1. The present study was designed to verify the ACh-mediated role in the action of C1X using cardiovascular and non-cardiovascular tissues taken from rats. 2. In the vasa deferentia preparations the muscular twitch induced by TNS was not changed by atropine, however in the presence of this drug, C1X induced a significant reduction of the height of the TNS-evoked twitch. 3. In the cardiorespiratory experiments, the administration of C1X produced a dose-dependent decrease in MAP, HR and RF. These effects were not changed by bilateral vagotomy and cervical sympathectomy. 4. The results obtained with atropine and with bilateral vagotomy and sympathectomy, attempt to delineate the possibility of a direct action of C1X. 5. All the evidence taken together does not support the hypothesis that C1X may be acting through an indirect action by releasing ACh.