副神经移位膈神经重建高位颈髓损伤比格犬呼吸功能及其呼吸中枢异化的研究

Tetraplegia and respiratory failure are the catastrophic complications in the patients with upper cervcial spinal cord injuries. Even if the mechanical ventilation therapy is available, most of them have poor quality of life, higher rate of complications and mortality. Therefore, it is important to reconstruct the respiratory function for them. Under the sponsor of the National Natural Science Fund projects, we successfully reconstructed the respiratory function in the SD rat with the upper cervcial spinal cord injury by accerory nerve transferring to the phrenic nerve.But after the neurotization, the neural transduction path and the mechanism that the plasticity of respiratory center and the lower motor neuron of accessory nerve are still not clear. Our team propose to creat the model of reconstructing the respiratory function in dog with the upper cervcial spinal cord injury by accerory nerve transferring to the phrenic nerve basis on the former reseach.. To observe the plasticity character of lower motor neuron of accessory nerve and respiratory center, and the connection between the plastic lower motor neuron of acessory and respiratory center. Meanwhile, we intend to compare the progress of respiratory center plasticity and the degree of recovery of respirotory function to make sure the relationship of them. To laying more reliable, more perfect foundation for the clinical appliaction.

高位颈髓损伤患者四肢瘫痪、呼吸功能丧失，依靠呼吸机辅助呼吸，生存质量低、并发症多、死亡率高，故重建其呼吸功能尤为重要。在国家自然基金面上项目的资助下，本项目组已采用副神经移位膈神经的方法，成功重建了高位颈髓损伤SD大鼠的呼吸功能。但神经移位后，神经传导通路的重建、副神经下运动神经元的异化及呼吸中枢的重塑等机制尚未明确。本项目组拟在原有工作的基础上建立副神经移位膈神经重建高位颈髓损伤比格犬呼吸功能的实验模型，观察呼吸功能重建过程中，副神经下运动神经元的异化部位及其特点，了解异化的副神经下运动神经元与呼吸中枢之间传导通路的重建方式，探讨呼吸中枢的重塑进程与呼吸功能恢复程度的关系。为将该方法过渡于临床提供更为翔实、可靠的实验依据。

通过建立副神经移位膈神经重建高位颈髓损伤比格犬呼吸功能的实验模型证实：比格犬副神经外侧支远端与膈神经主干起始端较为接近，可直接无张力缝接，且副神经移位膈神经 6 个月后可恢复高位颈髓损伤比格犬部分呼吸功能。利用辣根过氧化物酶及荧光金进行神经逆行示踪证实：副神经移位膈神经后支配比格犬膈肌的下运动神经元位于副神经脊髓核，即C1-C3脊髓前角部位。利用跨突触病毒示踪法，对神经移位后比格犬副神经脊髓核与延髓呼吸核之间传导通路的进行研究证实：副神经移位膈神经后支配高位颈髓损伤比格犬膈肌的下运动神经元与延髓呼吸核之间不存在传导通路。初步研究表明副神经移位膈神经重建高位脊髓损伤比格犬的呼吸功能系副神经脊髓核神经元或者其上级神经元发生重塑所致。