Deltamethrin induces mitochondrial membrane permeability and altered expression of cytochrome C in rat brain.

Deltamethrin is a type II synthetic pyrethroid insecticide and is used extensively. Numerous studies have demonstrated that deltamethrin can cause severe central nervous system symptoms. The mechanism of neuro-toxicity caused by deltamethrin is still poorly understood. This study investigated the effect of deltamethrin on the mitochondria-mediated apoptosis pathway in rat brain. The cortex and hippocampus mitochondrial membrane potential, permeability transition, expression of cytochrome c and activity of cytochrome c oxidase was assayed at 5, 24, 48 and 72 h following deltamethrin treatment. The study observed that the membrane potential, change of absorbance at 540 nm (A(540)), intensities of cytochrome c in mitochondria and activity of cytochrome c oxidase in the cortex and hippocampus of treated groups were significantly lower than those of the control group. The results of the study demonstrated that deltamethrin induced a decreased mitochondrial membrane potential and increased permeability, and reduced the expression of cytochrome c, thus depressing the activity of cytochrome c oxidase significantly. It indicates that deltamethrin may have an effect on mitochondria-mediated apoptosis of nerve cells in the rat brain. Copyright (c) 2007 John Wiley & Sons, Ltd.