Study on Blood-flow in Spinal Cord and Nerve Root

为阐明脊髓和神经根功能障碍的病理生理机制，本实验采用扫描电镜、透射电镜、电动机驱动高速摄影、微血流仪等技术，对成年狗脊髓和神经根的微细结构、循环动力学及脑脊液的作用进行了研究（电化学产生氢冲洗法）、氧分压计和肌电图仪（DANTEC-N2000）。在脑脊液中，滋养神经根的网状动、静脉与神经根鞘和底膜有疏松的联系.神经内膜间隙通过神经根鞘与蛛网膜下腔相通，神经根鞘很薄，脑脊液可透过.由于脑脊液的截留或排除，神经根中的血流量减少20%。根内毛细血管均为连续型，血神经屏障较强， ...更多信息 当神经根被压缩超过30 Grs时，由于屏障的破坏而发生血管源性水肿。静脉注射适量盐酸乙哌立松（4-乙基-2-甲基-3-哌啶基丙啡酮）可增加神经根血流量.阻断胸主动脉后，腰骶髓的血流量明显减少。诱发脊髓动作电位也严重降低，潜伏期延长.阻断胸主动脉后30 min，脊髓诱发电位恢复较快，但腰骶段脊髓尤其是灰质的血流量维持在降低水平的时间较长.脊髓也浸泡在脑脊液中，因为软脑膜可渗透脑脊液，并且Virchow-Robin血管周围间隙到达脊髓各处的端动脉和端静脉。脊髓中的血流量减少了约百分之十五，由于拦截或排除脑脊液。正常脑脊液的氧分压比脊髓中的压力高得多，后者由于脑脊液的拦截或排除而降低约15%。这些结果表明，脊髓和神经根与脑脊液密切相关，脑脊液流动状态的改变对脊髓和神经根有重要影响。少

The fine structure, circulatory dynamics and the role of cerebrospinal fluid in the spinal cord and nerve roots of adult dogs have been studied to clarify the pathophysiology of the spinal cord and nerve roots disturbance, using scanning electron micro-scope, transmission electron microscope, motor, driven high speed camera, micro-blood flow meter (electro chemically generated hydrogen washout method), partial oxygen pressure meter and electromygraphy (DANTEC-N2000).Results1. Redicular arteriesand veins nourishing nerve roots are loosely connected with the nerve root sheath and flooring in the cerebrospinal fluid.2. The endoneurial space is communicating with the subarachnoid space through the nerve root sheath which is very thin and permeable for the cerebrospinal fluid.3. The blood flow in the nerve root decreases by 20 percent due to interception or exclusion of the cerebrospinal fluid.4. Intraradicular capillaries are all continuous type and so the bloodnerve barrier is strong, but … More vasogenic edema occurs due to breakage of the barrier when the nerve root is compressed by more than 30 Grs.5. Intravenous injection of proper amount of Eperisone hydrochloride (4-Ethy-2-methy-3-piperidinopropiopheone) increases the blood flow in the nerve root.6. The blood flow in the lumbosacral spinal cord is reduced severely by interception of thoracic aorta. Evoked spinal cord action potentials are also decreased severely and the latency is prolonged.7. When the clamp is released 30 minutes after interception of thoracic aorta, evoked spinal cord action potentials recover quickly, but the blood flow in the lumbosacral spinal cord specially in the gray matter stays in the reduced level for longer time.8. The spinal cord is also soaked in the cerebrospinal fluid, because the pia mater is permeable for the cerebrospinal fluid and Virchow-Robin perivascular space reaches endarteries and endveins in all over the spinal cord.9. The blood flow in the spinal cord decreases by about 15 percent due to interception or exclusion of the cerebrospinal fluid.10. The partial oxygen pressure of the normal cerebrospinal fluid is considerably higher than the pressure in the spinal cord and the latter decreases by about 15 percent due to interception or exclusion of the cerebrospinal fluid.11. These results indicate that the spinal cord and nerve roots are closely concerned with the cerebrospinal fluid, and changes in the condition of the cerebrospinal fluid flow exert serious influence upon the spinal cord and nerve roots. Less