摘要
目的 观察幼兔心脏缺血预处理 2 4h对未成熟心肌缺血 /再灌注后Bcl -2mRNA表达的影响 ,探讨未成熟心肌保护第二窗形成的作用机理。方法 18只 3～ 4周龄幼兔 ,随机分为 3组 ,每组 6只 :Ⅰ组 ,正常对照组 ;Ⅱ组 ,缺血 /再灌注损伤组 ;Ⅲ组 ,缺血预处理组。建立活体心脏缺血 /再灌注损伤模型 ,Maclab/8s系统监测左心室发展压 (LVDP)、左室压上升及下降最大速率 (+dp/dtmax,-dp/dtmax)变化 ,原位免疫杂交 (ISH)方法检测心肌细胞内Bcl-2mRNA的表达。结果 缺血再灌注前 ,各组间LVDP、±dp/dtmax无显著性差异 (P >0 .0 5) ;再灌注 1h后 ,Ⅱ组的LVDP、+dp/dtmax和 -dp/dtmax恢复率分别为 (42 .81± 12 .56) %、(3 0 .67± 16.2 2 ) %和 (2 9.49± 10 .13 ) % ;Ⅲ组LVDP、+dp/dtmax及 -dp/dtmax恢复率分别为 (84.15± 13 .56) %、(69.49± 10 .3 6) %和 (58.3 7± 12 .45) % ,两组间有显著性差异 (P <0 .0 1)。Ⅱ组、Ⅲ组Bcl -2mRNA表达阳性细胞面积百分数分别为 (8.3± 2 .5) %、(76.3±13 .5) % ,两组间有显著性差异 (P <0 .0 1)。结论 缺血预处理可上调Bcl -2mRNA表达 ,参与未成熟心肌保护第二窗的形成 ,促进未成熟心肌缺血
Objective By exam ining t he expression of Bcl-2 gene 24 hours after ischemic preconditioning in neonatal rabbit heart undergoing myocardial ischemia/reperfusion to explore the mechanism of second window of protection of immature myocardium.?Method Eighteen China white rabbits (aged 3 to 4 weeks) were randomly divided in to 3 groups ( n =6 each group): GroupⅠ: normal control; GroupⅡ: ischemia/rep erfusion injury; Group Ⅲ: ischemia preconditioning. The changes of LVDP and ±d p/dt max in left ventricle were monitored with Maclab/8 s system. The expr ession of Bcl-2mRNA in myocardium was detected by hybridization in situ (ISH). ?Results There were no differences in LVDP and±dp/dt max between the 3 groups before myocardial ischemia ( P >0.05). After 1 hour of reperfusion, the recovery rate of LVDP, +dp/dt max and -dp/dt ma x were 42.81±12.56 %, 30.67±16.22 % and 29.49±10.13 % respectively in gr oupⅡ, significantly lower than those in group Ⅲ (84.15±13.56 %, 69.49±10.36% and 58.37±12.45% respectively, P <0.01). The area percentage of cardiomyo cytes positive for Bcl-2mRNA was 8.3±2.5 % and 76.3±13.5 % in groupⅡand grou p Ⅲ respectively, with the difference very significant( P <0.01).?Conclusion Ischemic preconditioning accelerates the recovery of LVDP and ±dp/dt in neonatal rabbit hearts after myocardial ischemia/reperfusio n by upregulating the expression of Bcl-2 gene.
出处
《徐州医学院学报》
CAS
2003年第6期477-480,共4页
Acta Academiae Medicinae Xuzhou
基金
江苏省麻醉学重点实验室开放课题 (K9843 )
