Cyclooxygenase 1 is required for pH control at the mouse gastric surface.

Background: Endogenous cyclooxygenase (COX) activity is required to maintain a relatively alkaline surface pH at the gastric luminal surface.

Aims: The purpose of this study was to determine which COX isoform, COX-1 or COX-2, is responsible for regulating the protective surface pH gradient and to test if COX inhibitors also had non-COX mediated effects in vivo.

Methods: Immunofluorescence and western blot analysis showed constitutive expression of both COX isoforms in the normal mouse stomach.