[Effects of sexual difference on the toxicity of ethylene oxide. I. Polyneuropathy]

Male and female Wistar rats were exposed to ethylene oxide (EO) at a concentration of 250 ppm, 6 hours a day, 5 days a week for 17 weeks simultaneously, and the sexual difference in susceptibility of the peripheral nerve to EO was investigated. Both male and female rats of the exposed group showed paresis of the hindlegs, but sexual difference did not affect the degree of this abnormality. In histopathological examinations, axonal degeneration of the myelinated fibers in the peroneal nerve, the nerve to the soleus muscle and in the gracile fascicles of the spinal cord was revealed. The nerve to the soleus muscle degenerated more severely than the peroneal nerve. Sexual difference played no part in the severity of the degenerations in each nerve or in the gracile fascicles. From these observations, we concluded that there was no significant difference in the susceptibility of the peripheral nerve to EO between male and female rats.