Neuronal apoptosis and related gene expression in response to Tetrandrine after acute spinal cord injury in rats / 中华创伤杂志

ABSTRACT

ObjectiveTo analyze the effect of Tetrandrine (Tet) on neuronal apoptosis and reletted gene expression after acute spinal cord injury (ASCI) in SD rats so as to provide experimental basis for treatment of ASCI.MethodsA total of 95 adult SD rats were.randomly divided into four groups,ie,control group ( n =5 ),ASCI group ( n =30),Tet treatment group ( Tet group,n =30) and methylprednisolone treatment group ( Mp group,n =30).The ASCI model was established with the aid of modified Allen method.The five rats from each group were sacrificed at postoperative 8 hours and 1,3,7,14,21 days respectively to observe the morphology of the injury spinal cord and expressions of cell apoptosis regulation genes ( Bcl-xl,Bcl-xs).The flow cytometry ( FCM ) was used to semiquantitatively analyze the apoptotic cells. ResultsExcept for the control group,the other three groups had morphological changes.Tissue edema,neuronal degeneration with some necrosis and marked inflammatory cell infiltration were founded in the ASCI group.Tissue injury was alleviated in the Tet group and was relatively much milder in the Mp group,with no obvious necrosis or inflammatory cell infiltration.Except for the control group,the number of Bcl-xs positive cells at the same time point was the most in the ASCI group in comparison with the Tet and Mp groups.Meanwhile,the expression of Bcl-xl in all groups reached the peak at day 7 post-injury.The semiquantitative analysis of the apoptotic cells displayed that,except for the control group,the number of apoptotic neurons in other three groups reached the peak at day 7 postinjury and then declined gradually.At the same time point,the apoptotic neurons in the Tet group were less than that in the ASCI group,but more than that in the Mp group. ConclusionsAfter ASCI,Tet plays an active role in intervening the expression of the apoptosis regulation gene and can evidently decrease neuronal apoptosis.Tet treatment can work within 7 days and should be given for ASCI as early as possible.However,Tet exerts weaker effect on ASCI in comparison with MP.