[Evaluation of the epithelial gastric mucosal barrier in gastric diseases using supravital staining of mucosal biopsies].

The permeability of the surface epithelium of the gastric corpus mucosa was investigated by the means of a supravital stain with trypan blue followed by fixation in Bouin's solution on fresh biopsies. While the epithelium of normal gastric mucosae remained unstained in nearly all cases, an increased permeability of varying degrees was frequently visible in biopsies from patients with gastritis. These changes were most pronounced in chronic atrophic gastritis and in gastritis with intestinal metaplasia and, above all, in acute erosive gastritis. Furthermore, the permeability of the mucosal barrier was markedly elevated in patients under an antiphlogistic or cytostatic therapy. Preincubation of the biopsies in a HCl-pepsin-solution (40 mEqu. HCl and 5 g pepsin per litre) or in a 1 per cent solution of sodium taurocholate, resulted in a marked elevation of permeability, even in normal mucosae, but there were, again, differences between normal and pathologically altered mucosae. The method described in this paper is thought to be a completion to the usually applied measurements of the mucosal barrier e.g. transmural electrical potential difference and ionic diffusion. The practical applicability primarily lies in the investigation of the mucosal barrier on the cellular level in various diseases, but also under the influence of newly developed drugs with damaging or mucoprotective effects.