Neurotoxic effects of 2,5-hexanedione on growing peripheral nerve axons of rat fetuses.

Peripheral nerves of rat fetuses were used to investigate the potential neurotoxicity of 2,5-hexanedione (2,5-HD) on developing axons. Pregnant female Sprague-Dawley rats were injected subcutaneously with 680 mg/kg of 2,5-HD once a day from day 12 of gestation (GD12) through GD16. On GD20 live fetuses were removed from the uterus, and the sciatic nerves were examined morphologically. Upon electron-microscopy affected nerves showed axons which were aggregated and fused together; the number of large axons was increased, but there were no axons aggregated with neurofilaments.