Cannabinoid CB1 receptors are involved in the regulation of rat gastric acid secretion

The effects of cannabinoid CB1 receptor activation (HU-210) and blockade (SR141716A) on gastric acid secretion were determined in anaesthetized rats with lumen perfused stomach. The selective CB1-receptor agonist HU-210 (0.01-0-1 mg kg−1, i.v.) did not affect basal acid secretion while causing inhibition (maximum reduction 74%) of the gastric acid secretion stimulated by pentagastrin (10μ kg−1, i.v.). The inhibitory effect of HU-210 was reversed by the selective cannabinoid CB1-receptor antagonist SR141716A (1 mg kg−1, i.v.), but not by the selective CB2-receptor antagonist SR144528 (1 mg kg−1, i.v.). These results suggest that cannabinoid CB1 receptors may mediate inhibitory effects on gastric acid secretion in the rat.