lactuside B降低脑缺血损伤大鼠海马和纹状体TRPM7 mRNA的表达

目的探讨lactuside B对大鼠脑缺血损伤后海马和纹状体TRPM7 mRNA表达的影响。方法采用大脑中动脉缺血再灌注损伤模型,SD雄性大鼠缺血2 h后再灌,分别于再灌后ip给予lactuside B 12.5,25和50 mg·kg-1,每天2次,每组1/2大鼠给药1 d,另1/2大鼠连续给药3 d,于末次给药后观察神经缺失症状并处死大鼠;RT-PCR技术检测大脑皮质和海马TRPM7 mRNA的表达。结果模型组大鼠各时间段神经缺失症状评分明显升高,海马和纹状体的TRPM7 mRNA表达均显著增加(P<0.01)。给予lactuside B12.5,25和50 mg·kg-11 d后,海马和纹状体TRPM7 mRNA表达分别为0.68±0.02,0.55±0.02和0.56±0.02,及0.32±0.02,0.25±0.01和0.35±0.01,与模型对照组比较均明显降低(P<0.01);给予lactuside B 12.5,25和50 mg·kg-1 3 d,海马和纹状体TRPM7 mRNA分别为0.29±0.02,0.18±0.01和0.26±0.01,及0.28±0.02,0.19±0.01和0.27±0.01,与模型对照组比较均明显降低(P<0.01)。结论lactuside B可降低海马和纹状体TRPM7基因的表达,提示该化合物对脑缺血损伤可能具有治疗作用。

Inhibitory effect of lactuside B on TRPM7 mRNA expression in hippocampus and striatum in cerebral ischemic rats

OBJECTIVE To explore the effect of lactuside B on transient receptor potential melastatin 7(TRPM7) mRNA expression in rat hippocampus and striatum after cerebral ischemia injury. METHODS The middle cerebral artery occulsion was used to make the ischemia (2 h) reperfusion injury model. After reperfusion, the rats were respectively ip given lactuside B 12.5, 25 and 50 mg·kg^-1 twice daily. Half of the rats of each group administered for 1 d while the rest administered continuously for 3 d. After the neurologic deficit score was observed in the last administration, the rats were sacrificed. The expression of TRPM7 mRNA on hippocampus and striatum was detected by RT-PCR. RESULTS Compared with sham group, the neurological lack symptom score in model group was significantly higher and the TRPM7 mRNA expression increased in hippocampus and striatum in rats. After lactuside B 12.5, 25 and 50 mg·kg^-1 was administered for 1 d, TRPM7 mRNA expression was decreased in hippocampus and striatum (hippocampus: 0.68±0.02, 0.55±0.02 and 0.56±0.02; striatum: 0.32±0.02, 0.25±0.01 and 0.35±0.01). TRPM7 mRNA expression was lower after lactuside B administered for 3 d (hippocampus: 0.29±0.02, 0.18±0.01 and 0.26±0.01; striatum: 0.28±0.02, 0.19±0.01 and 0.27±0.01). CONCLUSION Lactuside B can reduce TRPM7 gene expression in hippocampus and striatum, suggesting that lactuside B play a positive therapeutic and protective role.