The effect of i.v. indomethacin on the gastric mucosal electrical potential difference and blood flow in anaesthetized dogs

Indomethacin inhibits prostaglandin synthesis and causes gastric mucosal damage. The correlation between the gastric mucosal function and gastric blood flow was investigated. The intragastric liquid junction corrected potential difference (PD) across the stomach wall was used to characterize the gastric mucosal function. Mucosal blood flow was determined by the radiolabelled microsphere technique. Seven dogs were anaesthetized, intragastric PD was measured continuously and blood flow determined at basal condition during sympathetic activation, and after IV indomethacin (7.5 mg/kg). PD was unchanged during the basal period and during mild sympathetic activation. After indomethacin PD was reduced significantly (-40 +/- 6 mV to -20 +/- 5 mV, measured with gastric lumen negative, mean and SD, P less than 0.05). Mucosal blood flow decreased during sympathetic activation and a further significant reduction was seen after indomethacin. PD and flow reductions correlated (R = 0.92). As indomethacin given IV caused a parallel impairment of gastric mucosal function and blood flow, part of the indomethacin-related mucosal damaging effects might be due to the flow reduction.