罗哌卡因神经束内或周围给药对大鼠坐骨神经损伤的影响

目的 探讨罗哌卡因神经束内或周围给药对大鼠坐骨神经损伤的影响.方法 健康成年Wistar雄性大鼠72只,体重220～250 g,采用血管夹压迫一侧坐骨神经2 min的方法建立大鼠坐骨神经损伤模型,随机分为4组(n=18):损伤神经束内或周围注射生理盐水(Intra-NS组,Epi-NS组)、1%罗哌卡因(Intra-Ropi组,Epi-Ropi组)0.2 ml.于给药后1、3、7、14、21、28 d时测定坐骨神经功能指数(SFI),给药后14、28 d时测定坐骨神经传导速度(NCV),观察神经组织病理学结果.结果 Epi-NS组、Epi-Ropi组和Intra-NS组各时点SFI均依次升高(P＜0.05或0.01),给药后28 d时SFI恢复,各组问差异无统计学意义(P＞0.05),神经纤维和髓鞘无明显病理改变;与Epi-NS组、Epi-Ropi组和Intra-NS组比较,Intra-Ropi组给药后3～28 d SFI、给药后14、28 d时NCV降低(P＜0.05或0.01).给药后28 d时神经纤维粗细不一,髓鞘较薄.结论罗哌卡因神经束内给药可显著延迟大鼠损伤坐骨神经的恢复,而神经周围给药对神经恢复无影响.

Effect of epineural or intraneural injection of ropivacaine on acutely injured sciatic nerve in rats

Objective To investigate the effects of 1% ropivacaine injected epineurally or intraneurally on the recovery of sciatic nerve from acute injury in rats. Methods Seventy-two healthy male Wistar rats weighing 220-250 g were xandomly assigned into 4 groups ( n = 18 each): group Ⅰ epineural injection of normal saline(NS)(group C1); group Ⅱ intraneural injection of NS (group C2); group Ⅲ epineural injection of 1% ropivacaine (group Epi-R) and group Ⅳ intraneural injection of 1% ropivacaine (group Intra-R). The animals were anesthetized with intraperitoneal 3% pentobarbital 60 mg/kg. The sciatic nerve was exposed and crushed with blood vessel clamp for 2 min. NS or 1% ropivacaine 0.2 ml was injected epineurally or intraneurally after release of the clamp.Sciatic nerve function was measured and sciatic nerve function index (SFI) was calculated at day 1, 3, 7, 14, 21and 28 after operation. Six animals in each group were anesthetized on the 14th and 28th day after operation and the nerve conduction velocity (NCV) of the sciatic nerve was measured. The sciatic nerve was then removed for histologic examination. Results There was no significant difference in SFI and NCV at all time points among group C1 , C2 and Epi-R. SFI was almost normal on the 28th day after operation in the 3 groups. The NCV was significantly slower at day 14 and 28 after operation in intra-R group than in the other 3 groups. Conclusion Intra-neural injection of ropivacaine can significantly delay the recovery of sciatic nerve from acute injury.