ABSTRACT
Objective To examine the expression of protein kinase signaling cascade protein kinase B (Akt)-which plays an im-portant role in a number of key biological functions in cellular processes after spinal cord injury (SCI) in rats ,and its effects on SCI induced motor function defects ,and to provide the molecular mechanism for repairing SCI .Methods SCI was produced by extra-dural contusion using modified Allen′s stall with damage energy .The rats were divided into three groups :sham-operated group (Sham) ,interference group (Int) ,and control group (Con) .Using immunostaining studies ,Western blot analyses and real-time qualitative RT-PCR analyses ,we detected the changes of Akt expression at the protein and mRNA level in spinal cord tissues at 1 , 7 ,and 14 d after surgery ,and evaluated the presence and extent of neurological impairment after SCI by the BBB locomotor rating scale .Results The sham operated groups exhibited low expression of the Akt signaling at the protein and mRNA level ,and the ex-pressions increased following SCI .Compared to the animals in the sham operated groups ,prominently elevated level of Akt signaling was detected in the injured spinal cords of SCI group .LY294002 ,an inhibitor of phosphatidylinositol 3-kinase (PI3K) that initiates Akt phosphorylation ,prominently inhibited the expression of Akt produced by SCI and the spontaneous recovery of motor function after SCI .Conclusion Activated protein kinase signaling cascade Akt might be the important intervention aspects of involving in neuroprotective and repair process after SCI .