[Effects of polychlorinated biphenyls on regeneration of the peripheral nerve in rats].

The sciatic nerves was crushed at the mid-thigh level on the last day of 32 days oral administration of PCB. Nerve specimens were obtained from the crushed regions at 1, 2, 4 and 8 weeks after crushing. There was no significant difference between the experimental group and the control group in the density of regenerating fibers and distribution of fiber diameters at 1 and 2 weeks. At 4 and 8 weeks, however, the density of myelinated fibers was higher in the experimental group than in the control group. These results indicate that PCB may inhibit the regeneration of the crushed nerves. It is, however, still unknown that this adverse effects of PCB on the peripheral nerve depends on the disturbance of the remyelination or regeneration of the axon or both.