目的构建神经病理性痛动物模型,研究伏核注射天麻素对神经病理性痛的镇痛作用。方法实验采用左侧坐骨神经干部分结扎致神经损伤制作神经痛动物模型,观察伏核注射天麻素对伤害性热刺激和压力刺激诱发的大鼠后爪缩爪潜伏期的影响。结果左侧坐骨神经干部分结扎,引起双侧后爪缩爪潜伏期缩短,尤以10d后左侧明显(热板测试:t_左=7.35,P〈0.01;t_右=3.24,P〈0.05。Randall Selitto测试:t_左=5.05,P〈0.01;t_右=3.32,P〈0.05)。神经病理性痛大鼠伏核注射40μg/μL和20μg/μL天麻素引起双侧后爪缩爪潜伏期延长,但注射10μg/μL的天麻素没有显著性影响。结论天麻素在大鼠伏核对神经病理性痛具有镇痛作用。
Objective To determine the antinociceptive role of gastrodin in nucleus accumbens (NAc)of rats with neuropath- ic pain. Methods The left sciatic nerve of rat was Iigated to mimic neuropathic pain model,after which the present study observed the effect of intra-NAc injection of gastrodin on the hindpaw withdrawal latency (HWL)to noxious thermal and mechanical stimula- tion. Results The HWL in response to thermal and mechanical stimulation significantly decreased in bilateral hindpaws in the 10th day after left sciatic nerve ligation (thermal stimulation: tleft=7.35, P 〈0.01 ; tright= 3. 24, P 〈 0.05 ; mechanical stimulation: tleft= 5.50, P〈0.01 ;tright= 3.32 ,P(0.05). Intra-NAc injection of 40 or 20 μg/μL, but not 10 μg/μL of gastrodin markedly induced an increase in the HWL in rats with neuropathic pain. Conclusion Gastrodin contributes an important antinoeiceptive role to neuro- pathic pain in NAc of rats with mononeuropathy.