Effects of tetramethylpyrazine on expression of caspase 12 and apoptosis in rats with focal cerebral ischemia and reperfusion

Objective To observe the effects of tetramethylpyraxine( TMP) on expression of caspase 12 and apoptosis in rats with focal cerebral ischemia and reperfusion. Methods Forty-eight SD rats were randomly divided into sham operation group( S group),cerebral ischemia reperfusion group( I / R group),I / R + TMP1 group( 10 mg / kg·d),and I / R + TMP2 group( 30 mg / kg·d). Rat acute cerebral ischemia reperfusion injury was made through 2 hours of temporary middle cerebral artery occlusion followed with 22 hours of reperfusion. The rats were then treated for 7 days. S group and I / R group were given the same dose of normal saline. The volume of cerebral infarction,apoptosis,protein expressions of GRP78 and caspase 12 were analyzed by TTC,TUNEL and western blot,respectively. Neurobehavioral score was also determined. Results Compared with the S group,neural behavior score,apoptosis and cerebral infarction volume in I / R group were increased,the protein expressions of GRP78 and caspase 12 in I / R group were significantly increased( P 0. 05). Compared with the I / R group,neural behavior score,apoptosis and cerebral infarction volume was lower,protein expressions of GRP78 and caspase 12 in I / R + TMP group decreased dramatically( P 0. 05). Conclusion TMP can attenuate cerebral ischemia reperfusion injury,and the protective mechanism may be partly through regulating caspase 12 gene expression and reducing neuronal apoptosis.