Effect of venlafaxine hydrochloride in different preparations of isolated guinea-pig and rat organ tissues

1 A study was undertaken to know better the effects of venlafaxine hydrochl oride on the responses of isolated rat vas deferens to noradrenaline and do pamine, those of isolated rat uterus to serotonin and histamine, and those of isolated guinea-pig ileum to acetylcholine and histamine. 2 Venlafaxine hydrochloride increased the response of rat vas deferens to n oradrenaline but not to dopamine. Venlafaxine did not alter the response of rat isolated uterus to serotonin. In rat uterus, venlafaxine did not modif y the response to histamine but was able to increase it in guinea-pig ileum , An anticholinergic effect was observed with the lowest concentration test ed. 3 Although venlafaxine is a selective serotonine reuptake inhibitor in the central nervous system, serotonin uptake was not seen in the rat uterus, Th e anticholinergic effects observed in the present study might be consistent with some of the side-effects associated with venlafaxine.