Inhibitory effect of cannabinoid agonists on gastric emptying in the rat

Abstract.

We have studied the effect of WIN 55,212-2 (a psychoactive cannabinoid agonist), cannabinol (a non-psychoactive cannabinoid agonist), SR141716A, a cannabinoid CB₁ antagonist, and SR144528, a cannabinoid CB₂ antagonist, on gastric emptying in the rat. WIN 55,212-2 (0.1–5 mg/kg, i.p.) and cannabinol (0.1–25 mg/kg, i.p.) dose-dependently delayed gastric emptying while SR141716A (1 mg/kg and 5 mg/kg) and SR144528 (1 mg/kg) were without effect. SR141716A (1 mg/kg), but not SR144528 (1 mg/kg), counteracted the inhibitory effect of the two cannabinoid agonists. These results suggest that cannabinoid agonists delay gastric emptying through activation of cannabinoid CB₁ receptors, while the endogenous cannabinoid system does not seem to modulate gastric motility.