电压依赖性钙通道α2δ-1亚基在瑞芬太尼诱发切口痛大鼠痛觉过敏中的表达变化

ALTERATION OF EXPRESSION OF α2δ-1 SUBUNIT OF VOLTAGE-GATED CALCIUM CHANNELs IN RAT DORSAL ROOT GANGLIA IN REMIFENTANIL-INDUCED POSTOPERATIVE HYPERALGESIA

目的：观察背根神经节电压依赖性钙通道α2δ-1蛋白在瑞芬太尼诱发切口痛大鼠术后痛觉过敏中表达的变化。方法：体重180~220 g雄性SD大鼠64只,采用随机数字法分为8组（n=8）：对照组（C组）;瑞芬太尼组（R组）;切口痛组（I组）;瑞芬太尼＋切口痛组（M组）;切口痛＋鞘内注射NS组（E组）;切口痛＋瑞芬太尼＋NS组（F组）;切口痛＋瑞芬太尼＋Cavα2δ-1错义寡聚核苷酸组（G组）;切口痛＋瑞芬太尼＋Cavα2δ-1反义寡聚核苷酸组（H组）。瑞芬太尼颈部皮下输注剂量为80μg/kg（1 ml）,输注时间30 min;切口痛模型为右后足掌切口,深达肌肉层;鞘内分别注射NS、Cavα2δ-1错义寡聚核苷酸、Cavα2δ-1反义寡聚核苷酸。C、R、I和M组为实验1部分,E、F、G和H组为实验2部分。各组大鼠适应环境两天,于手术前48 h、24 h（T-2、T-1）,手术后6 h,24 h,48 h（T0-2）分别使用热辐射刺激仪和von Frey纤维丝进行热刺激缩足潜伏期（PWL）和机械刺激缩足阈值（PWT）测定。实验2大鼠分别于造模后6 h及24 h痛敏测定结束后进行鞘内注射。实验1和实验2痛敏测定完成后,取L4-6节段背根神经节,采用Western blot免疫印迹杂交法测定Cavα2δ-1蛋白的表达。结果：实验1：I组、R组和M组的术后各时段PWL、PWT均较C组降低,且M组较I组进一步降低,差异有统计学意义（P〈0.05）;M组背根神经节Cavα2δ-1蛋白表达水平较其余各组均高,差异有统计学意义（P〈0.05）。实验2：E组、F组、G组和H组的术后各时段PWL、PWT均降低,且F组、G组在T1-2较H组进一步降低,差异有统计学意义（P〈0.05）;H组背根神经节Cavα2δ-1蛋白表达水平较F组、G组降低,差异有统计学意义（P〈0.05）。结论：背根神经节Cavα2δ-1蛋白可能参与瑞芬太尼诱发切口痛大鼠的术后痛觉过敏的形成;鞘内注射Cavα2δ-1-反义寡聚核苷酸能延缓切口痛大鼠的术后痛敏。

Objective： To investigate the change of the expression of Cavα2δ-1 in the dorsal root ganglion（DRG） during postoperative remifentanil-induced hyperalgesia in rats with incisional pain. Methods： Adult, male Sprague-Dawley rats（180 ~ 220 g） were included in this experiment. In part Ⅰ, 32 rats were randomly divided into 4 groups（n = 8 each） using a random number table： Control group（group C）; Remifentanil group（group R）; Incisional pain group（group I） and Remifentannil ＋ incisional pain group（group M）. In part Ⅱ, 32 rats were randomly and equally divided into 4 groups： Incisional pain ＋ NS group（group E）; incisional pain ＋ Remifentannil ＋ NS group（group F）; incisional pain ＋ Remifentannil ＋ Cavα2δ-1mismatch oligodeoxynucleotide group（group G）; incisional pain ＋ Remifentannil ＋ Cavα2δ-1 antisense oligodeoxynucleotide group（group H）. In partⅠand part Ⅱ, all rats received behavioral tests, paw withdrawal threshold（PWT） and paw withdrawal latency（PWL）. DRGs at L4-6 were immediately removed for determination of expression of Cavα2δ-1 protein by Western blot. Results： Part 1： Compared with group C, PWT was significantly decreased and PWL was shortened at each time point after operation in group I, R and M, and the PWT and PWL in group M was significantly lower than in group I; Compared with other groups, the expression level of the Cavα2δ-1 protein in the DRG was up-regulated in group M. Part 2： Compared with T-2 and T-1, the PWT and PWL were significantly decreased at T0-2 in all groups, and the PWT and PWL in group F and G were significantly lower than in group H at T1-2; Compared with group F and G, the expression level of Cavα2δ-1 protein in the DRG was decreased in group H. Conclusion： The up-regulation of the Cavα2δ-1 expression level in the DRG may be involved in the development of remifentanil-induced hyperalgesia in rats with incisional pain; Intrathecal injection Cavα2δ-1 antisense oligodeoxynucleotide could relieve the hyperalgesia induced by remifentanil.