Is prostacyclin subserving a vasodilator effect of methoxamine involving alpha adrenoreceptors?

The influence of methoxamine on the contractile tension of isolated rat abdominal aorta, and on its capacity to produce a platelet antiaggregating substance, were explored. Methoxamine stimulated platelet antiaggregation and diminished arterial tone. The last action was blocked by phentolamine as well as by inhibitors of cyclo-oxygenase and prostacyclinsynthetase.