CCI模型中大鼠后足不同位置机械痛阈值的比较

为获得测定大鼠CCI机械痛阈的最佳位置,笔者选取符合条件的SD雄性大鼠,进行坐骨神经慢性挤压性神经损伤模型制作,测定其足底不同位置机械痛阈,并比较其效果。结果为大鼠CCI手术前,1,2,3号位置的痛阈值无显著性差异(P>0.05);CCI手术后,对于手术侧后肢,1,2号位置与3号位置进行比较显示均存在极显著性差异(P<0.001),1号位置与2号位置进行比较无显著性差异(P>0.05);对于未手术侧后肢,1,3号位置与2号位置比较均无显著性差异(P>0.05),但1号位置与3号位置间存在显著性差异(P<0.05)。结果表明,2号位置为CCI模型机械痛阈测定的最佳位置。

Pain-related mediators underlie incision-induced mechanical nociception in the dorsal root ganglia

Approximately 50-70% of patients experience incision-induced mechanical nociception after sur- gery. However, the mechanism underlying incision-induced mechanical nociception is still unclear. Interleukin-10 and brain-derived neurotrophic factor are important pain mediators, but whether in- terleukin-10 and brain-derived neurotrophic factor are involved in incision-induced mechanical no- ciception remains uncertain. In this study, forty rats were divided randomly into the incision surgery （n = 32） and sham surgery （n = 8） groups. Plantar incision on the central part of left hind paw was performed under anesthesia in rats from the surgery group. Rats in the sham surgery group re- ceived anesthesia, but not an incision. Yon Frey test results showed that, compared with the sham surgery group, incision surgery decreased the withdrawal threshold of rats at 0.5, 3, 6 and 24 hours after incision. Immunofluorescence staining in the dorsal root ganglia of the spinal cord （L3-5） showed that interleukin-10 and brain-derived neurotrophic factor were expressed mainly on small- and medium-sized neurons （diameter 〈 20 pm and 20-40 pm） and satellite cells in the dorsal root ganglia of the spinal cord （L3-5） in the sham surgery group. By contrast, in the surgery group, high expression of interleukin-10 and brain-derived neurotrophic factor appeared in large-sized neurons （diameter 〉 40 pm） at 6 and 24 hours after incision surgery, which corresponded to the decreased mechanical withdrawal threshold of rats in the surgery group. These experimental findings suggest that expression pattern shift of interleukin-10 and brain-derived neurotrophic factor induced by inci- sion surgery in dorsal root ganglia of rats was closely involved in lowering the threshold to me- chanical stimulus in the hind paw following incision surgery. Pain-related mediators induced by in- cision surgery in dorsal root ganglia of rats possibly underlie mechanical nociception in ipsilateral hind paws.

针刺对慢性偏头痛大鼠趋化因子C-C配体2和C-X-C基序配体1的影响研究

目的:观察针刺对慢性偏头痛大鼠(CM)的足底机械痛阈、三叉神经脊束核尾侧亚核(Sp5C)中趋化因子C-C配体2(CCL2)、C-X-C基序配体1(CXCL1)水平的影响,为临床运用针灸治疗偏头痛提供一定依据。方法:将28只大鼠随机分为对照组、模型组、针刺组、非经非穴组,每组7只。采用隔日颈背部皮下重复注射硝酸甘油(NTG)建立慢性偏头痛大鼠模型。每日对针刺组和非经非穴组进行针刺治疗,20 min/次。采用Von Frey仪器测定大鼠足底机械痛阈,采用酶联免疫吸附测定法检测各组Sp5C中CCL2、CXCL1的水平。结果:与对照组比较,模型组大鼠足底机械痛阈明显降低(P<0.01);与模型组比较,针刺组大鼠足底机械痛阈明显升高(P<0.01)。与对照组比较,模型组的Sp5C中CCL2、CXCL1的水平升高(P<0.01);针刺组较模型组CCL2、CXCL1的水平降低(P<0.01)。结论:针刺可以通过下调CCL2、CXCL1趋化因子的表达,从而减轻偏头痛的疼痛程度,发挥对偏头痛的治疗作用。

电针对大鼠慢性神经源性痛的治疗作用

目的 观察大鼠慢性神经源性痛时的抬腿潜伏期变化及电针对其治疗作用。方法 72只SD大鼠制作慢性神经源性痛模型 ,随机分为对照组、慢性疼痛组、电针治疗组各 2 4只。电针取坐骨神经压迫侧环跳、阳陵泉穴。痛阈测定采用热辐射测痛法 ,术前、术后d2、d4、d7、d14、d2 8测后肢抬腿潜伏期 ,电针组并于每次电针前后各测 1次抬腿潜伏期。结果 电针治疗组术后d2开始抬腿潜伏期缩短 ,与慢性疼痛组基本相似。随电针次数增加 ,抬腿潜伏期逐渐延长 ,到d14坐骨神经压迫侧与慢性疼痛组相比明显延长 (P <0 .0 5 )。d2 8已显著延长 ,但仍低于实验对照组假手术侧 (P <0 .0 5 )。结论 多次电针后对坐骨神经压迫引起的慢性神经源性痛大鼠的热痛敏具有明显的逆转作用。