Renal anaphylaxis. I. Antigen-initiated responses from isolated perfused rat kidney

Renal anaphylaxis. I. Antigen-initiated responses from isolated perfused rat kidney. Isolated perfused rat kidneys were passively sensitized by addition of either mouse ascitic fluid containing monoclonal IgE against dinitrophenol (DNP) or DNP-specific purified IgE. After washing the organ, defined doses of DNP-bovine serum albumin were given as bolus injection via the kidney artery. Antigen challenge of IgE-sensitized kidneys resulted in a dose-dependent increase of perfusion pressure starting with 5 µg antigen (2.46 ± 0.2 mm Hg) and reaching a maximum at dose higher than 100 7µg (10.3 ± 1.6 mm Hg) (N = 4, means ± 1 sd). A decrease of glomerular filtration rate was also observed which reached a plateau at 100 µ% antigen (-68.5 ± 2.9%) (N = 4). Regardless of the dose of antigen used, the urinary protein excretion markedly increased for the first five minutes following antigen injection and returned to basal values after 10 minutes. The total amounts of histamine, PGE 2 and paf-acether (platelet-activating factor) released upon antigen challenge (1 mg) for 15 minutes reached maximal values of 405 ± 21.1 ng, 286 ± 19.4 pg and 12.3 ± 3.2 ng (N = 5), respectively. None of these hemodynamic and biochemical effects were observed using IgG 1 monoclonal antibodies or when the ascitic fluid containing monoclonal IgE used to sensitize the organ was heated at 56°C for two hours. Thus, we have described a pure IgE-dependent rat kidney anaphylaxis. Antigen challenge markedly altered renal parameters and triggered the release of various mediators from the organ, suggesting that type I-hypersensitivity reactions may play a role in renal pathophysiology.