不同作用时程高压氧治疗对神经病理性疼痛大鼠的影响

Effect of Different Hyperbaric Oxygen Exposure Time on Antinociceptive Response in Rat Neuropathic Pain Model

目的探讨不同作用时程高压氧治疗对神经病理性疼痛大鼠的影响。方法成年雄性sD大鼠28只，采用随机数字表法，将其均分为4组：假手术组（S组）、坐骨神经慢性缩窄手术组（CCI组）、高压氧治疗5d组（HBO5d组）、高压氧治疗10d组（HBO10d组）。将HBO5d组和HBO10d组大鼠至于高压氧舱，以0．0125MPa／min的速率向舱内匀速加压直至目标压力并保持60min。然后匀速减压至正常大气压。从术后第1天开始高压氧治疗，连续5d或10d，1次／d。s组和CCI组单纯放入氧舱100min而不接受治疗。于术前ld，术后1，2，3，7，14，21，28d测定机械缩足反射阈值（MWT）和热缩足反射潜伏期（TWL）。术后28d取材观察其脊髓的免疫组化指标，对一氧化氮合酶（NOS）表达进行比较。结果与s组比较，其他3组MWT降低，TWL缩短（P〈0．05）。与CCI组比较，HBO5d组和HBO10d组术后28dMWT升高，TWL延长（P〈0．05），术后21d2组的MWT和TwL差异无统计学意义（P〉0．05）。术后21～28d，HBO5d组和HBO10d组MWT和TwL差异有统计学意义（P〈0．05）。CCI后，NOS的表达明显增加，与CCI组比较，HB05d组与HBO10d组增加更显著（P〈0．05）。而HBO5d与HBO10d组差异无统计学意义（P〉0．05）。结论不同作用时程高压氧治疗均可减轻大鼠神经病理性疼痛，并且作用时间越长可能镇痛效果越持久。

Objetcdve To investigate the effect of antinociceptive response induced by different hyperbaric oxygen （HBO） exposure in an animal model of neuropathic pain. Methods A total of 28 healthy male SD rots were randonaly divided into four groups （n =7 ） ： Group S （ sham group ）, Group CCI （chronic constrictive injury group）, Group HBO 5 d （HBO duration for five days group） and Group HBO 10 d （HBO duration for ten days group）. Group CCI, group HBO 5 d and group HBO 10 d received the surgery of CCI, while group S only received sham operation. Rats of group HBO 5 d and group HBO 10 d received HBO one time per day for 5 days or 10 clays since the 1st day after surgery. After putting rots inside the HBO chamber, the pressure was increased at a rate of 0.012 5 MPa/min to the desired pressure and maintained for 60 minutes. Rats of group S and group CCI were simply placed inside the chamber for approximately 100 rain, but without HBO. The mechanical withdrawal threshold （MWT） and thermal withdrawal latency （TWL） of all animals were measured at 1 d before CCI, 1 d, 2 d, 3 d, 7 d, 14 d, 21 d and 28 d after CC1 respectively. Results Compared with group S, MWT was significantly decreased and TWL was significantly shortened in other groups. Compared with group CCI, MWT was elevated and TWL was prolonged significantly in group HBO 5 d and HBO 10 d （P 〈 0.05 ）. Compared with group HBO 5 d, MWT was elevated and TWL was prolonged in group HBO 10 d （P 〈 0.05 ） after postoperative 21 days. There was no significant difference in alteration of the antinociceptive response effect between groups HBO 5 d and HBO 10 d within postoperative21 days （P 〉 0.05）. After CCI treatment, the NOS expression was increased. NOS expression was significantly decreased in tile HBO 5 d and HBO10 d groups. There was no significant difference be- tween HBO 5 d and HBO 10 d. Conclusion Different HBO durations influenced antinociceptive effects on CCI rats with neuropathic pain.