Studies On The Toxic Damage Of Weaning Rat's Brain And Protective Effect Of NAC By Perinatal Exposure To Lead In Female Rats

To investigate the toxicity damage of weaning rat's brain induced by female rats perinatal exposure to lead and protective effect of N-Acetylcysteine, fifteen pregnant SD female rats were randomly separated into 3 groups, which were given in the drinking water from pregnant. groupâ… (lead acetate 300mg/L), groupâ…¡(lead acetate 300mg/L +NAC 20mmol/L), groupâ…¢was control group. We observe the effects of exposure to lead to development of nervous system and nervous behavior in neonatal rats by using neural development praxiology, and the activity of GSH-Px, SOD, CAT, TChE and MDA content were measured in brain and blood serum of weaning rats, and histological structure and ultrastructure of hippocamp was analysed. The content of lead and trace element(zinc,iron,copper,selenium,manganese) in blood, brain, ossature, liver and kidney were analyzed respectively by inductively couple plasma-mass spectrometry(ICP-MS).The results showed that, in comparison with control group, significant decrease in the body weight growth, the brain weight growth, physical development (the appearance day of incisor eruption and eye opening), the early nervous reflex and forward function development of rat pups are observed (P<0.05). The activity of GSH-Px,SOD,TChE in brain both decreased significantly(P<0.05) and MDA content increased significantly (P<0.05); The activity of GSH-Px,SOD,CAT,TChE in blood serum both decreased significantly(P<0.05) and MDA content increased significantly(P<0.05); The histopathological studies showed that the appearance of hippocamp neuron was eumorphism, there was no evident histopathological change between groups; the ultrastructure studies showed that some nerve cells karyopycnsis, chromatin dissolved lightly, nucleopore increased mitochondria swell, cristae disappeared. In comparison with control group, The content of lead in tissues of lead exposure group increased significantly(P<0.01), The content of zine in tissues of lead exposure group decreased significantly(P<0.01), the content of iron in liver,the content of selenium in kidney and the content of iron,copper,selenium in ossature of lead exposure group decreased significantly(P<0.05). Compared the NAC antagonistic group with the poisoning group, significant decrease in the body weight growth, the early nervous reflex and forward function development of rat pups are observed (P<0.05);The activity of SOD in brain of NAC antagonistic group increased significantly(P<0.05) and MDA content in brain of NAC antagonistic group decreased significantly(P<0.05); The activity of SOD,CAT,TChE in blood serum of NAC antagonistic group both increased significantly(P<0.05) and MDA content decreased significantly(P<0.05); The content of lead in tissues of NAC antagonistic group has a significant decrease (P<0.05).This study indicated that lead exposure when female rats perinatal damaged brain development of weaning rats obviously. NAC have shown to protected the developing brain damage caused by lead exposure when female rats perinatal.