大鼠慢性缺血性肢体疼痛模型的探索性构建

Exploratory construction of chronic ischemic limb pain model in rats

目的通过测定大鼠机械痛阈(paw withdrawal thresholds,PWTs)、足跖肿胀程度(paw thickness)、足跖部皮温(paw skin temperature)以及足跖部局部血流情况(paw blood flow),探索一种简便、可靠的大鼠慢性缺血性肢体疼痛模型的构建方法。方法将16只SD大鼠完全随机分为假模型组(sham CILP组,n=8)和慢性缺血性肢体疼痛模型组(CILP组,n=8)。慢性缺血性肢体疼痛模型组采用O型圈下肢近膝关节处小压力值缓慢加压,加压强度为1.2-2.2 N,加压每日1次,一次加压30-40 min,连续3周造模。检测两组大鼠对患侧于造模前,加压后6、13、20 d的PWTs以及足跖部肿胀程度、皮温和局部血流情况。结果造模20 d完成加压后,CILP组大鼠患对侧PWTs均显著低于同期假模型组(P<0.01);CILP组大鼠患侧足跖部厚度均显著高于同期假模型组和同期对侧(P<0.01);CILP大鼠患侧足跖皮温加压后显著低于同期假模型组(P<0.01);CILP大鼠对患侧足跖平均血流量均显著低于同期假模型组(P<0.01)。结论在大鼠下肢处通过长时间缓慢加压,能够有效造成慢性缺血性肢体疼痛的情况,从而建立大鼠慢性缺血性疼痛模型。

Objective By measuring paw withdrawal thresholds(PWTs),paw thickness,paw skin temperature,and paw blood flow in rats,we explored a simple and reliable method for constructing a chronic ischemic limb pain model in rats.Methods Sixteen rats were randomly divided into a sham chronic ischemic limb pain group(sham CILP group,n=8)and a chronic ischemic limb pain group(CILP group,n=8).The chronic ischemic pain model group used O-ring lower limbs near the knee joint to slowly pressurize the limb.The compression intensity was 1.2-2.2 N,with compression performed once a day as well as once a week for 30-40 min for 3 consecutive weeks.The PWTs and degree of swelling,skin temperature,and local blood flow of the two groups of rats before and after modeling were measured at 6,13 and 20 days after compression.Results After 20 days of modeling,the ipsilateral and contralateral PWTs of the CILP group were significantly lower than those of the sham CILP group(P<0.01).The ipsilateral paw thickness of the CILP group was significantly thicker than that in the same period in the sham CILP group as well as the contralateral paw thickness of the CILP group(P<0.01)over the same period.Furthermore,the ipsilateral skin temperature of the CILP group was significantly lower than that of the sham CILP group(P<0.01).In addition,the average ipsilateral blood flow of the CILP group was significantly lower than that of the sham CILP group during the same period(P<0.01).Conclusions Long-term low pressure in the lower limbs of rats can effectively cause chronic ischemic limb pain,as demonstrated by the establishment of a rat model of chronic ischemic limb pain.