美国研究人员利用3种不同康复方法,成功帮助因脊髓损伤而瘫痪的实验鼠重新获得了行动能力,为下肢瘫痪人群的康复提供了新的思路。
美国加利福尼亚大学洛杉矶分校的研究人员20日在英国《自然杂志神经学专刊》上报告说,他们针对瘫痪小鼠同时使用了药物、电刺激和常规锻炼3种康复方法,成功使小鼠重新走动,甚至能够在跑步机上跑动。
研究人员说,值得一提的是,在康复治疗过程中,实验鼠因脊髓完全受损而被截断的神经纤维并未再生。在这种情况下,瘫痪鼠仅借助上述3种康复方法也能恢复行动能力,这说明对于脊髓损伤的瘫痪患者来说,即便无法实现神经纤维再生,也能恢复部分的行动能力。
研究负责人雷吉·埃杰顿介绍说,脊髓中含有重要的神经回路,负责产生驱动肢体肌肉的节奏性活动。以前的研究都试图直接修复患者脊髓内的这一神经回路,但相关研究中最后获得的肢体行动能力恢复效果都不理想。
此次,他们采取的是“三管齐下”法,将瘫痪鼠置于运动状态的传步带上,然后向其注射作用于神经递质血清素的药物,并实施低水平的电流刺激。结果发现,电刺激加上传步带传递给肢体的运动感,触发了受损脊髓内的神经回路,促使实验鼠产生了走步甚至跑动的动作。经过几个星期的这种综合疗法,实验鼠最终获得部分行动能力。(生物谷Bioon.com)
生物谷推荐原始出处:
Nature Neuroscience 20 September 2009 | doi:10.1038/nn.2401
Transformation of nonfunctional spinal circuits into functional states after the loss of brain input
Grégoire Courtine1,2, Yury Gerasimenko3,4, Rubia van den Brand1,2, Aileen Yew5, Pavel Musienko1,2,4, Hui Zhong3, Bingbing Song6, Yan Ao6, Ronaldo M Ichiyama3, Igor Lavrov3, Roland R Roy3,6, Michael V Sofroniew5,6 & V Reggie Edgerton3,5,6
After complete spinal cord transections that removed all supraspinal inputs in adult rats, combinations of serotonergic agonists and epidural electrical stimulation were able to acutely transform spinal networks from nonfunctional to highly functional and adaptive states as early as 1 week after injury. Using kinematics, physiological and anatomical analyses, we found that these interventions could recruit specific populations of spinal circuits, refine their control via sensory input and functionally remodel these locomotor pathways when combined with training. The emergence of these new functional states enabled full weight-bearing treadmill locomotion in paralyzed rats that was almost indistinguishable from voluntary stepping. We propose that, in the absence of supraspinal input, spinal locomotion can emerge from a combination of central pattern-generating capability and the ability of these spinal circuits to use sensory afferent input to control stepping. These findings provide a strategy by which individuals with spinal cord injuries could regain substantial levels of motor control.
1 Neurology Department, University of Zurich, Zurich, Switzerland.
2 Rehabilitation Institute and Technology Center Zurich, Zurich, Switzerland.
3 Department of Physiological Science, University of California Los Angeles, Los Angeles, California, USA.
4 Motor Physiology Laboratory, Pavlov Institute of Physiology, St. Petersburg, Russia.
5 Department of Neurobiology, University of California Los Angeles, Los Angeles, California, USA.
6 Brain Research Institute, University of California Los Angeles, Los Angeles, California, USA.