心肌营养素-1基因转移对大鼠脊髓损伤后红核神经元的保护作用

Protective effects of cardiotrophin-1 gene transfer on rubrospinal neurons in rats after spinal cord injury

目的:观察腺病毒介导心肌营养素-1基因转移对大鼠脊髓损伤(spinalcordinjury,SCI)后红核神经元的保护作用。方法:制备大鼠颈3脊髓外侧索横切(C3Hx)模型,损伤区植入明胶海绵饱和的不同成分治疗及对照溶液。分为AdCMV-CT1组、空白对照组、AdCMV-eGFP对照组及正常对照组。荧光金(FG)于C2注射,1,4,8周脑切片,荧光显微镜下红核神经元记数观察红核神经元的存活。结果:在损伤后1～4周,标记红核神经元数几乎无变化。损伤后8周,损伤组、Adv-eGFP组、Adv-CT1组标记神经元分别减少31%,32%,19%。Adv-CT1组与损伤组相比,差异有显著性意义(P<0.05)。表明脊髓损伤后,红核神经元存在迟发性损伤。Adv-CT1在脊髓中长期表达,明显支持红核神经元的存活。结论:腺病毒介导心肌营养素-1基因转移长时间支持红核神经元的存活。

AIM:To observe the influency of cardiotrophin-1 adenoviral gene transfers in protecting rubrospinal neurons of rats with spinal cord injury(SCI). METHODS:Gel foams saturated with different solutions were respectively injected into the injured regions of the corresponding groups that included AdCMV-CT group,blank control group,AdCMV-eGFP group and normal control group.Fluord-gold(FG) was injected into C2.Brian sections were made after 1,4 and 8 weeks to observe the survival of rubrospinal neurons under fluorescence microscope.RESULTS:Following the injuy to the C3 spinal cord of rats,the number of FG-labeled rubrospinal neurons hardly changed at 1～4 weeks, but the number of rubrospinal neurons was decreased by 31%in the injured group, 32%in the Adv-eGFP group,and 19%in the Adv-CT1 group after 8 weeks. There was a significant difference between the injured group and the Adv-CT1 group(P< 0.05),indicating that rubrospinal neurons had delayed impairment following SCI,and that the long-term expression of Adv-CT1 remarkably supported the survival of rubrospinal neurons.CONCLUSION:Cardiotrophin-1 adenoviral gene transfers have prolonged support to the survival of rubrospinal neurons.