Effects of adenosine preconditioning on expression of B lymphocytes/leukemia-2 and bcl-2 associated X protein following the spinal cord ischemia-reperfusion injury of rats

Objective To study the expression levels of B lymphocytes/leukemia-2 (bcl-2) and bcl-2 associated X protein (bax) following ischemia-reperfusion injury and their action mechanism on apoptosis for investigating the protection of spinal cord I-R injury by means of adenosine preconditioning.Methods The experimental model was established in rats through cross-clamping of abdominal aorta inferior to the left renal artery.Twenty-seven rats were randomly divided into three groups:group A (n =9),sham group; group B (n =9),I-R group ; and group C (n =9),administration with adenosine group.Spinal cord function was assessed by the Modified Tarlov Scale at 12,24 and 48 h after reperfusion.At 48 h after reperfusion,histologic analysis was done by hematoxylin and eosin (HE) and Nissl staining,ultrastructures were observed under transmission electron microscopy,and the expression levels of bcl-2 and bax pro tein and mRNA were detected by using Western blotting and real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) respectively.Results HE staining and Nissl staining results showed:group B showed extensive spinal cord injury such as cell edema and dissolution of Nissl substance when compared to group C; the number of apoptotic cells in group C was less than that in group B.Western blotting and RT-qPCR results showed adenosine could reduce bax expression and increase the bcl-2 expression.Conclusion Adenosine can reduce spinal cord I-R and improve neurological function. Key words: Spinal ischemia;  Reperfusion injury;  Apoptosis ;  B leukemia/lymphocytes-2 ; bcl-2 associated X protein