Effect of cimetidine on gastric mucosal barrier in dogs.

The effect of cimetidine on the gastric mucosal barrier (GMB) was investigated in adult mongrel dogs with a Heidenhain pouch. A linear correlation was found between the net flux of Na+ and H+, and transmucosal electrical potential difference (PD). The PD was thus considered to be a good indicator for the degree of impairment of the GMB which can be determined easily with high reproducibility. When irrigated with HCl alone, there was a slight, though not significant, upward tendency of the PD following intravenous cimetidine. The destruction of the GMB during perfusion with HCl plus sodium taurocholate resulted in a marked reduction of the PD. This response of the PD was significantly reduced by the injection of cimetidine. These results indicate that cimetidine protects the GMB from impairments by bile acid.