Tracing of regenerating nerve along its length using adenovirus vector

实验一：将含LacZ基因的重组腺病毒载体接种于Wistar大鼠正中神经(正中神经组)和胫神经(胫神经组)近端断端。在不同时间点，取脊髓C5~Th1或L2~L6及相应的背根节和臂丛、骶丛进行X-Gal染色。结果表明，LacZ基因特异性地定位于切断神经的运动神经元和感觉神经元，B-Gal顺行标记神经元的轴突，直至神经修复部位的远端。检测两组背根节神经元、运动神经元和周围神经轴突的起始时间、峰值时间、持续时间和B-Gal标记数目。实验二：尺、正中神经束交叉至肌皮运动部件远端切端，提供良好的肘关节独立屈曲。我们推测，某些神经亲和性或可塑性不仅在大脑中起作用，而且在脊髓中也可能起作用，以进行神经交叉，从而诱导定向神经再生。方法：以41只雄性Wistar大鼠的上肢为实验对象。结果/统计：I组：肌皮染色根位于C5-C7，中位数在C6-Th1，尺骨在C8-Th1。这些根水平的神经与人类的相同。肌皮神经和尺神经之间无神经根水平重叠。II组：尺神经远端感染，C5-Th1神经根染色，近端尺神经与远端肌皮神经粘连(7/7)。经远端肌皮神经感染标记为C8和Th1根(7/7)。总结：交叉远端尺神经感染的结果表明，C5-C7神经元可能通过C8-Th1根将出芽的轴突发送到近端尺神经，可能是通过脊髓内。

Experiment I.Adenoviral vectors containing LacZ gene were administrated to the cut proximal stumps of median nerves (median nerve group) and tibial nerves (tibial nerve group) using Wister rats. At different time points post transfection, the sections of spinal cord of C5 to Th1 or L2 to L6 and the corresponding DRGs and brachial or sacral plexuses nerves were processed for X-gal staining. The results show that LacZ gene specially targeted to the motor and sensory neurons of the transected nerves and that B-gal anterogradely labeled the axons of the neurons as far as to the distal of the nerve repairing sites. The initial time, peak time, persisting period and the number of B-gal labeling of DRG neurons, motor neurons and peripheral nerve axons in the two groups were also detected.Experiment IIHYPOTHESIS : Crossing of the ulnar or median nerve funiculi to the distal cut end of musculocutaneous motor components provides independent good flexion of the elbow. We hypothesized that some neurotropism or plasticity may work not only in brain but also in spinal cord for nerve crossing which should invite misdirectional nerve regeneration.METHODS : We used upper limb of 41 male Wistar rats. RESULTS/STATISTICS: Group I: Stained roots for musculocutaneous located in C5-C7, median in C6-Th1 and ulna in C8-Th1. These root level innervations are same with those human. There was no innervating root level overlap between musculocutaneous and ulnar nerves. Group II : Infection through the distal ulnar nerve demonstrated staining of C5-Th 1 roots and proximal ulna nerve coapted to the distal musculocutaneous nerve(7/7). Infection through distal musculocutaneous nerve labeled C8 and Th1 roots(7/7).SUMMARY POINT : Result of the infection from crossed distal ulnar nerve shows new fact that C5-C7 neurons may send sprouting axons to proximal ulnar nerve through C8-Th1 roots probably through inside of spinal cord.