[In vivo and in vitro study of (N-piperidinomethyl)-2-chromanne on pre- and postsynaptic alpha-adrenoreceptors in the rat].

The alpha-adrenoceptors blocking effect of (N-piperidinomethyl)-2-chromanne was studied in vivo and in vitro in the rat. In the pithed rat, (N-piperidinomethyl)-2-chromanne (1 mg/kg i.v.) antagonized the pressor effects induced by alpha agonists. (N-piperidinomethyl)-2-chromanne competitively antagonized the pressor effects of M7 (alpha 2-agonist) and cirazoline (alpha 1-agonist). (N-piperidinomethyl)-2-chromanne antagonized the inhibitory effects of clonidine on presynaptic alpha 2-receptors in stimulated pithed rats. On the vas deferens of the rat (N-piperidinomethyl)-2-chromanne antagonized the inhibitory effects of clonidine on the twitch response produced by electrical stimulation and also the contractions induced by phenylephrine. This derivate appears to be an alpha 1 and alpha 2 blocking agent.