VPA-induced Autism Model Cortex Bcl-2, Bax Expression In Rat

Objective：By observing the expression of Bcl-2and Bax in cerebral cortex in sodiumvalproate-induced animal model of the autism of rats, we want to explore the role of Bcl-2andBax in pathogenesis of the autism.Methods：Females received a single intraperitoneal injection of sodium valproate(VPA,600mg/kg) on the12.5day after conception in the experiment，the pups as modelgroup;and control females were injected with physiological saline at the same time, the pups ascontrol group.Sodium valproate was dissolved in saline at a concentration of250mg/ml.Observe and test the physical development, social interaction, communication andstereotyped, repetitive patterns of behaviors of the pups. The test of physical development: ratweight,eye opening time, the direction of the trend and swimming coordination capacity; socialinteraction:to follow companions and physical contact with companion; communication and no-communication:self-modification and regional heuristic; stereotyped, repetitive patterns ofbehaviors： rats circling,bouncing,fur finishing body.By using the Nissl staining,immunohistochemistry and image analysis techniques,we observed the expression of Bcl-2andBax in cerebral cortex of those baby rats on the1th,7th,14th,28th,56thday after being born (writtenas P1、P7、P14、P28、and P56for short).Results：Compared with the control group, the model group’s rats showed an obviouslygrowth retardation and abnormal behavior. Nissl staining showed the number of corticalneurons decreased on the day of P1、P7, and then rapidly increased on the14th day. P28、P56is still higher than control group.By testing all the immunohistochemistry sample’s integratedoptical density(IOD) of the Bcl-2and the Bax, it is positively expressed the cells in corticallayer of two groups animals decreased from P1day to P14day（P<0.001）,then remainedstable form on the day of P28（P>0.05）. Compared with the control group, the IOD for Bcl-2of the model group decreased much more on all of those samples at every time point（P<0.001）.But the result of the Bax shows a little bit different. Compared with the controlgroup, the number of the IOD which is tested from the immunohistochemistry of the Bax isincreased from the day of P1to P7（P<0.001）,and rapid decreased on the day of P14（P<0.001）,then remained stable form on the day of P28（P>0.05）.For the normal control group’s rats,the ratio of Bcl-2/Bax,which is highest on P1, then decreased as age. P7is stillgreater than1.Later P14,the ratio is stabilized,approximately1. For the model group’s rats,theratio of P7is lowest than the other, P1is higher than P7. P14is highest of all. P28decreased,andthen stabilized.Conclusion：The sodium valproate-induced model group rats’ cerebral cortex neuronsanti-apoptotic capacity is decreased,especially in the early postnatal。...