【Animal modeling】-Exploratory construction of a rat model of chronic ischemic limb pain

  Objective To explore a simple and reliable method to construct a rat model of chronic ischemic limb pain by measuring the mechanical pain threshold, the degree of swelling of the plantar, the skin temperature of the plantar and the local blood flow of the plantar.

  Methods Sixteen SD rats were randomly divided into sham model group (sham CILP group, n = 8) and chronic ischemic limb pain model group (CILP group, n = 8). In the chronic ischemic limb pain model group, the O-ring was used to slowly pressurize the lower limb near the knee joint with a small pressure value, the compression strength was 1.2-2.2 N, the compression was once a day, and the compression was 30-40 times a day. min, modeling was established for 3 consecutive weeks. The PWTs of the affected side of the two groups of rats before modeling and 6, 13, and 20 days after compression, as well as the degree of swelling of the soles of the feet, skin temperature and local blood flow were detected.

  Results After 20 days of modeling, the PWTs of the contralateral side of the rats in the CILP group were significantly lower than those in the sham model group (P < 0.01); The model group and the contralateral side of the same period (P < 0. 01); the skin temperature of the affected side of the CILP rats after compression was significantly lower than that of the sham model group (P < 0. 01); The blood flow was significantly lower than that of the sham model group (P < 0.01).

  Conclusion The chronic ischemic limb pain can be effectively caused by long-term slow pressure on the lower limbs of rats, thus establishing a rat model of chronic ischemic pain.