中文摘要：

目的：研究福尔马林致病后大鼠脊髓和背根神经节（dorsal root ganglion，DRG）内降钙素基因相关肽（calcitonin gene-related peptide，CGRP）的时空变化规律，为探讨CGRP在伤害性信息传递中的机制和作用提供实验依据。方法：选取健康成年正常SD大鼠54只随机分为生理盐水对照组和福尔马林实验组；实验组为右侧足底皮下给予0．1mL5％福尔马林后，分别存活15min、30min、1h、3h、6h、12h、24h和72h（n=6），免疫组化结合图像分析技术观测CGRP在脊髓腰段及L4～6DRG的表达变化。结果：正常DRG、脊髓前角和后角内CGRP有一定的基础表达。福尔马林致病后3hDRG的CGRP表达上升，12h～24h迭峰值，72h基本降低到正常；福尔马林致痛后6h脊髓后角CGRP的表达上调，24h达到高峰，72h降低至正常；脊髓前角CGRP未见明显变化。结论：福尔马林致痛引起DRG和脊髓的CGRP的表达呈现一定的时空模式，可能是其参与伤害性信息传递的机制之一。

英文摘要：

Objective： To observe the temporospatial expression changing laws ofcalcitonin gene-related peptide （CGRP） in the spinal cord and dorsal root ganglion （DRG） after subcutaneouly formalin injection in rats hind planta. Methods： 54 healthy adult SD rats were distributed into physiological saline group and experimental groups, while experimental groups were subdivided randomly into 15 min, 30 min, 1 h, 3 h, 6 h, 12 h, 24 h and 72 h groups （n=6） which were treated with 5% formalin 100 μL injected into rat hind planta. The expression and distribution of CGRP in the lumber spinal cord and L4-6 DRG were detected by immunohistochemical method and image analysis technique. Results： CGRP was expressed in normal anterior and posterior horns of spinal cord and DRG. The expression of CGRP in DRG neurons was up-regulated in 3h group after subcutaneouly formalin injection. However, changes of CGRP in DRG peaked at 12 h-24 h groups, then decreased to normal level at 72 h group. The expression of CGRP increased in the lamina II of spinal cord at 6 h group, and peaked at 12 h -24 h groups, then decreased to normal level at 72 h group. There were no changes in the CGRP-positive spinal ventral motoneurons of all groups. Conclusions： The changes of CGRP presented a temporospatial pattern in the spinal cord and DRG after formalin injection, which may be one of mechanisms that participated in the nociceptive signal transmission.