Demonstration of ochratoxin A in kidneys of pigs and rats by immunofluorescence microscopy.

Ochratoxin A was localized in the kidney of pigs and rats by means of immunofluorescence microscopy after short-time exposure. Antibody against ochratoxin A was obtained from rabbits after repeated injections of bovine serum albumin-ochratoxin A conjugate. Ochratoxin A was localized exclusively in the proximal tubule. Light microscopically, necrosis and desquamation of epithelial cells in the pig kidneys were restricted to the proximal tubule where the toxin was found. The investigation had demonstrated conclusively that the proximal tubule is the target part of the nephron in ochratoxin A-induced mycotoxic nephropathy.