Vasoactive properties of prostaglandin compounds on the in vitro human basilar artery.

The action of six prostaglandins A1, E1, (A2, E2, F1 alpha, F2 alpha) on in vitro human basilar artery circumferential strips was evaluated to assess relative vasoreactivity. Degree of contraction was compared with 5-hydroxytryptamine (5-HT), hitherto the most active in this laboratory. The three most vasoactive prostaglandins were E1, E2, and F2, alpha. The three PGs giving highest magnitude of response were F1 alpha, F2 alpha, and E2. Most were more active when compared to 5-HT. Vasodilation did not occur. Because of their vasoconstrictive qualities, prostaglandins may participate in arterial vasospasm. It is postulated that prolonged vasoconstriction may lead to vasospasm and that the latter may result from one or more autacoids acting along or synergistically.