Effect of psychological stress on gastric potential difference in man

This study investigated the effect of three different mental stress tests on gastric transmucosal electric potential difference (GPD). GPD measurement was carried out in six healthy volunteers using the agar-KCl bridges method during dichotomous listening, the ringing of a telephone and 90 dB noise. Cardiac, pulmonary and psychological responses to stress were evaluated at the same time. During the stress period, two of the subjects had no change in GPD as well as no extragastric modification due to the stressor. The four other volunteers had a significant stress-induced fall in GPD (12.5 + 5.6 mV) with a simultaneous acceleration of heart and respiration rates and an increase in systolic blood pressure and anxiety feelings which were evaluated on a visual scale. Such mental stress, possibly mediated by autonomous nervous system, may cause some gastric mucosa changes inducing the retrodiffusion of H+ ions and a fall in GPD. This model could be useful in therapeutic research into the prevention and treatment of stress-induced gastric lesions.