Objective   To explore relationship between the brain developmental injury and c-fos expression caused by MMC.

  Methods   The injury effects of MMC on cultured neurocytes derived from neonatal Wistar rat were studied by means of microscope and fluoroscopy. The effects of MMC on the c-fos expression of meron and glia were studied using immunocy-tochemistry method.

  Results   Apoptosis characteristics, such as condensed cytoplasm and margination of nuclear chromatin, pyknotic nuclei and swollen mitochondria were found after cultured glia was exposed to MMC. The percentage of Fos-positive neuronal and glial nuclei began to increase at 0.5 h after cultured cerebral neurocytes exposed to 0.3μmol/L MMC continously, increased gradually with the time of exposure to MMC prolonging and kepthigh level in hours. Experimental groups bering exposed to MMC for 10 min, 2 hr, 6 hr, the percentage of positive c-fos neuronal nuclei was 8.78%, 68.26%, 64.95%, respectively and that of glial nuclei was 7.74% 66.61%, 72.52%, respectively.

  Conclusion   It was concluded that MMC can induce the expression of c-fos and apoptosis of cultured neurocytes. The apoptosis may be mediated by c-fos expression.