Abstract
Masugi Nephritis induced in rats was employed as experimental model to investigate the possible effects of rheumatoid factor on in-vivo antigen-antibody reactions. Rats injected simultaneously with rheumatoid arthritis serum or Hodgkin's serum (containing high titer of Rheumatoid factor) and rabbit nephrotoxic serum showed a three or four-fold increase with time compared with rats injected with nephrotoxic serum alone. Normal human serum had no effect on the proteinuria produced by a standard dose of nephrotoxic serum. IgM (presumably rheumatoid factor) in glomerular of rat injected the RF serum was detected by immunofluorescence along the glomerular basement membrane with the nephrotoxic serum and rat complement (C3 and C1q) . Rheumatoid factor activity was also recovered by elution from glomeruli isolated from rat kidneys 48 hrs. after the injection of rheumatoid arthritis serum or Hodgkin's disease serum and nephrotoxic serum. Histological changes of kidneys of rat 48 hrs, after injection with rheumatoid arthritis serum (particularly malignant rheumatoid arthritis serum) and nephrotoxic serum showed cortical necrosis (4/6) and severe glomerular changes, compared with the other groups.
Thus, the deposition of RF in the glomeruli seemed to closely relates to chronicity and sererity of the Masugi nephritis.
