Effects of the mycotoxins citrinin and ochratoxin a on hepatic mixed-function oxidase and adenosinetriphosphatase in neonatal rats.

The effects of citrinin, ochratoxin A, or a combination of the two mycotoxins on the hepatic monooxygenase system and on hepatic and renal adenosinetriphosphatase (ATPase) activities were examined in neonatal rats exposed to a single treatment of one or both toxins. Animals received (po) 25 mg/kg citrinin, 1 mg/kg ochratoxin A, or 25 mg/kg citrinin plus 1 mg/kg ochratoxin A within 24 h of birth. Pups were killed 12 d later. Citrinin or ochratoxin A alone did not affect hepatic ATPase. Renal oligomycin-sensitive Mg2+-ATPase was inhibited to the same degree by ochratoxin A and the combination treatment. A synergistic effect of the two mycotoxins was observed on renal Na+-K+-ATPase. Significant effects, due to the mycotoxin interaction, were also observed on cytochrome P-450 content, NADPH-dependent dehydrogenase, and NADPH-cytochrome c reductase.