Vasoconstriction induced by delta 9-tetrahydrocannabinol on the perfused rabbit ear artery

Periarterial incubation of delta 9-Tetrahydrocannabinol (THC, 15.0--30.0 mM) to the "in vitro" perfused central artery of the rabbit ear, induced sustained contractions related to the dose and reverted after washing. Simultaneously, the artery responses to transmural electrical stimulation were blocked and the effects of intravascular injection of noradrenaline were additive to the constriction induced by THC. Either reserpine treatment or chronic artery denervation blocked the vasoconstriction induced by THC. These results indicate that THC may induce vasoconstriction in the perfused artery of the rabbit through the release of noradrenaline from sympathetic nerve terminals.