The effect of delta1-tetrahydrocannabinol on the release of (3H-(-)-noradrenaline from the isolated vas deferens of the rat.

1 The amount of tritium released upon transmural stimulation of the isolated vas of the rat incubated with [(3)H]-Delta(1)-tetrahydrocannabinol (THC) (2.8 muM) was significantly greater than the non-stimulated overflow.2 There was no difference between non-stimulated overflow and the effect of transmural stimulation of vasa equilibrated with [(14)C]-sorbitol (6.5 mg/ml).3 The difference between non-stimulated and stimulated efflux from vasa equilibrated with [(3)H]-Delta(1)-THC was abolished in rats pretreated for 24 h with 6-hydroxydopamine (250 mg/kg).4 The amount of tritium released upon transmural stimulation of the vas incubated with [(3)H]-noradrenaline (6 muM) was significantly greater than the non-stimulated overflow.5 Delta(1)-THC (560 nM and 14 muM) caused a significant dose-dependent reduction of both non-stimulated and stimulated tritium efflux, especially the latter.