GYKI-12743 a new postsynaptic vascular alpha-adrenoceptor antagonist.

Using the pithed rat preparation it has been proven that GYKI-12743 exerted its alpha-adrenergic blocking action only at the postsynaptic vascular level in the cardiovascular system. This new molecule failed to antagonize the presynaptic alpha 2-adrenoceptors of the cardiac sympathetic nerve endings. Thereby it was possible to demonstrate the first vasoselective postsynaptic adrenoceptor antagonist which potentially might be interesting in the cardiovascular therapy.