目的探讨鞘内注射cAMP反应元件结合蛋白(CREB)反义寡核苷酸(ODN)对坐骨神经结扎小鼠痛行为的影响。方法鞘内置管成功C57BL/6雄性小鼠24只,体质量20~25g,随机分为4组(n=6),生理盐水组(NS组),CREB同义寡核苷酸组(S组),CREB错义寡核苷酸组(M组),CREB反义寡核苷酸组(A组)。制备坐骨神经慢性挤压伤(CCI)模型,造模后第1~6天,4组分别鞘内给予生理盐水5μl、同义寡核苷酸5μg/5μl、错义寡核苷酸5μg/5μl、反义寡核苷酸5μg/5μl,每天1次。于造模前、后第1,3,5,7,10,14,17,21天测量CCI小鼠同侧足底机械刺激痛阈值(PWMT)和热辐射刺激潜伏期(PWTL)。结果A组小鼠1—7d内的疼痛阈值维持在基础值水平[第7天,PWMT:(0.81±0.20),(1.00±0.19)g.P〉0.05;PWTL:(5.96±0.69),(6.93±1.08)s,P〉0.05]。在小鼠CCI后的第10天,A组损伤侧足出现疼痛[第10天,PWMT:(0.56±0.19),(1.00±0.19)g,P〈0.05;PWTL:(3.93±0.28),(6.93±1.08)S,P〈0.05],但是与NS组[第10天,PWMT:(0.56±0.19),(0.37±0.08)g,P〈0.05;PWTL:(3.93±0.28),(3.14±0.45)s,P〈0.05]、s组、M组相比,疼痛明显减轻,并且持续到术后第21天。结论在CCI诱导的神经病理性疼痛的发展阶段连续鞘内注射CREB反义寡核苷酸可以完全抑制给药期内痛行为表现,并且在停止给药后15d仍有明显缓解疼痛的作用;
Objective To investigate the effects of intrathecally cyclic AMP response element-binding protein(CREB) antisense oligodeoxynucleotide (ODN) on neuropathic pain behaviors. Methods Using mouse model of neuropathic pain induced by chronic constriction injury of sciatic nerve (CCI) ,24 male C57BL/6 mice successfully received intrathecal catheter implantation and without motor dysfunction were randomly divided into 4 groups( n = 6) :Saline group ( NS), CREB sense ODN group ( S ), CREB missense ODN group ( M ), CREB antisense ODN group(A). Mice in NS,S,M and A were intrathecally treated with Saline 5μl,Sense ODN 5μg/5μl, Missense ODN 5μg/5μl and Antisense ODN 5μg/5μl once daily on day 1 -6 after CCI respectively. Paw withdrawal mechanieal threshold (PWMT) and paw withdrawal thermal latency(PWTL) were tested on day 1 before CCI and day 1,3,5,7,10,14,17,21 after CCI. Results Mice in A group maintained the pain thresholds in the baseline and lasted at least 7 days after CCI(7 d,PWMT: (0.81 ±0.20)g vs (1.00 ±0. 19)g, P〉0.05; PWTL : ( 5.96± 0.69 ) s vs ( 6.93 ± 1.08 ) s, P 〉 0.05 ). The withdrawal thresholds in the ipsilateral hind paws of the mouse were significantly lower than baseline in A group on day 10 after CCI ( 10 d, PWMT : (0.56± 0.19 ) g vs (1.00±0.19)g,P〈0.05; PWTL: (3.93±0.28)svs (6.93±1.08)s,P〈0.05). Compared with NS group (10 d,PWMT: (0.56±0.19)g vs (0.37±0.08)g, P〈0.05; PWTL: (3.93 ±0.28)s vs (3.14 ±0.45)s, P〈 0.05) ,S group,M group,the withdrawal thresholds of A group was significantly elevated on day 10 after CCI. These effects lasted up to at least day 21 after CCl. Conclusion Intrathecally treated with CREB antisense ODN in the development of neuropathic pain induced by CCI completely improved pain behaviors during the course of injection,and the effects of relief pain lasted at least 15d after no injection.