[Mercuric chloride-induced enteropathy in the rat: a model of gastrointestinal disease with immunologic pathogenesis].

Protein-loss into the gastrointestinal tract is a feature of many different diseases, a number of which are immunologically mediated, e.g. systemic lupus erythematosus or Crohn's disease. The pathogenic mechanism of protein-losing enteropathy in diseases without obvious enterocyte injury are unknown. Brown-Norway-rats (BN-rats) were gavaged with low doses of HgCl2 for 39 weeks. Within 2 weeks, the intestines showed strong linear staining for IgG and IgA along vascular and intestinal basement membranes. Granular deposits containing IgG and C3 were present along intestinal basement membrane only in the late stages of the experiment; only in these animals increased intestinal protein loss as measured by fecal Cr-51 excretion was found. These findings suggest that immune complex deposition along the intestinal basement membrane can lead to protein-losing enteropathy. This disease may be used as a model for the study of immunologically mediated intestinal disease.