Interactions of minoxidil with vasoconstrictive agents in isolated rat tail artery.

The role of minoxidil in the inhibition of norepinephrine, serotonin, angiotensin and potassium chloride-induced vasocontractions was investigated. Isolated rat tail artery was used as an experimental model. It was found that the examined drug reduced serotonin angiotensin and norepinephrine-evoked rises in perfusion pressure, being the most potent inhibitory agent towards serotonin. Minoxidil failed to inhibit the response of isolated vessels to potassium chloride. The minoxidil may be involved in the inhibition of serotonergic (5-HT2) receptors.