Absence of an anaphylactic vasopermeability mechanism for immune complex deposition in the Heymann nephritis of rats.

The existence of an anaphylactic mechanism favouring the deposition of circulating immune complexes in Heymann's nephritis and its possible inhibition by disodium cromoglycate (DSCG) and antihistamines was studied. No animal produced anti-renal tubular anaphylactic antibodies (IgE and IgGa classes) and no histamine and PAF (platelet-activating factor) release were obtained when buffy coat cells (BCC) were challenged with the soluble Fx1A antigenic fraction. However, PAF was obtained from phagocytozing leucocytes. Total histamine after boiling 10(7) BCC was less than 20 ng. The frequency of nephritis and quantity of immune deposits in the glomerular basement membrane were similar in treated and control groups. Our results show that, contrary to the data obtained in acute serum sickness of rabbits, an anaphylactic mechanism in Heymann's nephritis does not seem to exist. Accordingly the treatment with antihistamines and/or disodium cromoglycate did not produce any beneficial effect upon the course of the disease.