Experimental autoimmune glomerulonephritis was induced in inbred WKY/NCrj rats and Wistar (closed colony) rats by a single injection of isologous or homologous soluble antigens from glomerular and tubular basement membranes. Glomerular and tubular basement membranes were trypsin digested and applied to an affinity column to which rabbit antibodies to bovine nephritogenic antigen had been coupled. The adsorbed fraction was nephritogenic when it was injected into rat footpads with Freund's complete adjuvant. Glomerulonephritis with long-lasting proteinuria and haematuria developed 2 to 3 weeks after the injection, and it was characterized histologically by endocapillary hypercellularity of mononuclear cells, capsular adhesion, sclerosis of capillary tufts, and crescent formation. Immunofluorescence study revealed the linear deposition of rat IgG along the glomerular basement membrane. Some rats with the nephritis had pulmonary hemorrhage. These results suggest that this experimental model is similar to the experimental glomerulonephritis induced in rats by bovine nephritogenic antigen, and to human anti-glomerular basement membrane antibody-induced glomerulonephritis including Goodpasture's syndrome.