Pathomechanism of radicular pain in lumbar radiculopathy.

将脂肪、髓核(NP)和纤维环(AF)移植到L_6水平的大鼠硬膜外间隙。术后对机械刺激的戒断反应阈值和对热刺激的戒断反应潜伏期。应用免疫组织化学、NADPH-黄递酶组织化学和原位杂交技术检测白介素1、磷脂酶A2和一氧化氮合酶的表达。结果表明，同种异体脂肪移植不会产生痛觉过敏。同种异体移植的NP和NP+AF分别表现出机械性和热性痛敏。虽然白介素1在所有涂抹的组织中都有表达，但PLA2仅在涂抹的NP和NP+AF.周围观察到，而NOS仅在涂抹的周围显著增加。分别将同种异体坐骨神经移植于坐骨神经的NP组和NP+AF组的坐骨神经局部注射L或美帕林，观察其对伤害性刺激的敏感性。只有NP组大鼠表现出机械性痛觉过敏。在NP+AF组，注射L-NAME可引起机械性痛敏。NP组和NP+AF组注射L-NAME后产生的机械性痛敏，注射美帕林后均恢复正常。综上所述，PLA2和NO在腰椎间盘突出症神经根性疼痛的发病机制中可能起着重要但不同的作用。

Fat, nucleus pulposus (NP) and anulus fibrosus (AF) were allografted into the epidural space at L_6 level in the rat. Withdrawal response thresholds to mechanical stimuli and withdrawal response latencies to thermal stimuli on the tail postoperatively. Interleukin-1, PLA_2 and NOS were examined in the applied tissues using immunohistochemistry, NADPH-diaphorase histochemistry and in situ hybridization. In results, allografted fat did not produce hyperalgesia. Allografts of NP and NP+AF showed evidence of mechanical and thermal hyperalgesia, respectively. Although interleukin-1 was demonstrated in all applied tissues, PLA_2 was only observed around the applied NP and NP+AF.NOS was only markedly increased around the applied. The NP group (allografted NP placed on the sciatic nerve) and NP+AF group (NP+AF,respectively) were mede to evaluate the sensitivities to noxious stimuli following local sciatic nerve administration of L-NAME or mepacrine into the operated site. Only rats in the NP group showed evidence of mechanical hyperalgesia. Injection of L-NAME resulted in evidence of mechanical hyperalgesia in the NP+AF group. Mechanical hyperalgesia, which was produced in the NP group and after injection of L-NAME in the NP+AF group, both of which returned to normal after mepacrine injection. In conclusion, it appears that PLA_2 and NO play important but different roles in pathomechanisms of radicular pain in lumbar disc herniation.