Citrinin-induced mitochondrial permeability transition.

The effects of mycotoxin citrinin on Ca2+ efflux and membrane permeabilization were studied in isolated rat liver mitochondria. The efflux rate observed when in presence of ruthenium red was higher when citrinin was added. Swelling experiments demonstrated Ca(2+)-dependent membrane permeabilization by citrinin. Catalase, butylhydroxitoluene (BHT), and dithiothreitol (DTT) did not protect swelling caused by Ca2+ plus citrinin. The protection conferred by ATP-Mg2+ and cyclosporin A in the latter experiments are strong indications of pore formation. These results suggest that citrinin can induce permeability transition by a mechanism that does not involve oxidative damage.