Abstract Experimental data suggest that the endogenous cannabinoid system is involved in gastric function in different animal species. In most of them, CB1 receptors have been localized on vagal terminals innervating the external wall of the stomach. We aimed at studying the putative presence and distribution of these receptors in the human gastric mucosa. To this end, we first performed Western blotting, RT-PCR, in situ hybridization, and immunohistochemical analysis of CB1 protein distribution in biopsy samples of healthy individuals. To determine the precise cell populations expressing CB1 receptors, we performed double immunofluorescence plus confocal microscopy analysis of the same samples. Our results show that CB1 receptors are present...