Effects ofL-tetrahydropalmatine on the expressions of bcl-2 and bax in rat after acute global cerebral ischemia and reperfusion

Abstract

To investigate the effect ofL-Tetrahydropalmatine (L-THP) on the expressions of bcl-2, bax and neuronal apoptosis after cerebral ischemia and reperfusion, 60 Wistars, rats were randomly divided into 3 groups: sham-operation group (group S,n=20), ischemic-reperfusion group treated with saline (group I,n=20) and ischemia-reperfusion group treated, with,L-THP (group T,n=20). The rat model of global cerebral ischemia and reperfusion was induced by Pulsinelli's four-vessel occlusion method. The expression of bcl-2 and bax mRNA was detected by in situ hybridization and reverse transcriptional polymerase chain reaction (RT-PCR). The number of apoptotic neurons was examined by terminal deoxynucleotidyl-transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) method. Compared with group S, the expression of bcl-2 and bax mRNA in group I was increased significantly (P<0.01), and the number of apoptotic neurons increased either (P<0.01). AfterL-THP treatment, the expression of bcl-2 mRNA was up-regulated (P<0.01) and that of bax mRNA was down-regulated (P<0.01) the number of apoptotic neurons was decreased (P<0.01). Our results indicated that bcl-2 may suppress apoptosis and bax promote apoptosis after cerebral ischemia and reperfusion.L-THP could ameliorate cerebral ischemia and reperfusion damage by reducing the apoptosis through regulating bcl-2 and bax.

Keywords

cerebral ischemia and reperfusion / neuronal apoptosis / expression of bcl-2 and bax / L-tetrahydroalmatine

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