Galtrey Clare M, Fawcett James W
Centre for Brain Repair, Department of Clinical Neurosciences, Cambridge University, Cambridge, UK.
J Peripher Nerv Syst. 2007 Mar;12(1):11-27. doi: 10.1111/j.1529-8027.2007.00113.x.
The majority of human peripheral nerve injuries occur in the upper limb but the majority of studies in the rat are performed in the hindlimb. The upper and lower limbs differ in dexterity and control by supraspinal systems, so an upper limb model is a better representation of the common form of human injury. The purpose of this study was to further develop a rat model involving lesions of the median and ulnar nerves. To produce different degrees of misdirection of axons following nerve repair, we studied nerve crush, cut and repair of the two nerves, and cut and repair with crossover. Assessment of functional recovery was performed using a battery of motor and sensory tests: the staircase test, which assesses skilled forepaw reaching; grip strength meter, which assesses grip strength; pawprint analysis, which assesses toe spread and print length; horizontal ladder, which assesses forepaw placement during skilled locomotion; modified Randall-Selitto device and electronic von Frey probes, which assess fine touch; and cold probes, which assess temperature sensation. All tests revealed deficits in forepaw function after nerve injury except the print length and modified Randall-Selitto device. The time course of functional recovery was observed over 15 weeks. The final degree of functional recovery achieved was related to the misdirection of axon regeneration. The tests that most clearly revealed the effects of axon misdirection on function were the skilled paw reaching and grip strength tests. The lesion model and functional tests that we have developed will be useful in testing therapeutic strategies for treating the consequences of inaccurate axon regeneration following peripheral nerve injury in humans.
大多数人类周围神经损伤发生在上肢，但大鼠的大多数研究是在后肢进行的。上肢和下肢在灵活性以及脊髓上系统的控制方面存在差异，因此上肢模型能更好地代表人类常见的损伤形式。本研究的目的是进一步开发一种涉及正中神经和尺神经损伤的大鼠模型。为了在神经修复后产生不同程度的轴突错向，我们研究了两条神经的挤压、切断和修复，以及交叉切断和修复。使用一系列运动和感觉测试来评估功能恢复情况：阶梯试验，评估熟练的前爪够取能力；握力计，评估握力；爪印分析，评估趾展和印长；水平梯子试验，评估熟练运动过程中的前爪放置；改良的兰德尔 - 塞利托装置和电子冯·弗雷探针，评估精细触觉；以及冷探针，评估温度感觉。除了印长和改良的兰德尔 - 塞利托装置外，所有测试均显示神经损伤后前爪功能存在缺陷。在15周内观察了功能恢复的时间进程。最终实现的功能恢复程度与轴突再生的错向有关。最能清楚显示轴突错向对功能影响的测试是熟练前爪够取和握力测试。我们开发的损伤模型和功能测试将有助于测试治疗策略，以治疗人类周围神经损伤后轴突再生不准确所带来的后果。
