中文摘要：

目的探讨基质金属蛋白酶3（MMP3）在创伤愈合过程中的变化及其意义。方法采用本研究前期建立的方法分离大鼠皮肤伤后伤口液和真皮多能干细胞。取伤后1天伤口液作为创伤修复启动微环境刺激真皮多能干细胞,24h后通过免疫组化方法检测MMP3表达水平的变化。同时制作单纯创伤和难愈创伤动物模型,观察伤口局部炎性细胞浸润、肉芽组织形成、成纤维细胞数量、表皮再上皮化程度等创伤愈合过程变化,并通过免疫组化和图像分析方法观察伤后不同时相（3、5、7、10、14天）伤口组织MMP3含量变化。结果创伤早期伤口液作用后,真皮多能干细胞MMP3表达显著增加。正常大鼠皮肤组织可见一定量的MMP3表达,阳性细胞主要为表皮细胞、毛囊外根鞘细胞、真皮成纤维细胞、血管内皮细胞等。单纯创伤大鼠伤后各时相点MMP3表达均显著增加,尤以真皮组织为著,其峰值在伤后5～7天。难愈创伤组大鼠伤后各时相点MMP3含量亦显著增加,但其表达峰值延迟,为伤后10天,且伤后3、5、7天真皮组织的表达水平显著低于单纯创伤组。结论MMP3是一种重要的创伤愈合调节分子;高表达MMP3可能是真皮多能干细胞参与创伤修复的途径之一。

英文摘要：

Objective To explore the changes and significance of matrix metalloproteinase 3 （MMP3） during wound healing in rat. Methods Wound fluids and dermal pluripotent stem cells （DPSCs） were isolated with routine method from rats, and they were purified and expanded. Wound fluid was collected on the first day to serve as wound microenvironment, then the responses of DPSCs to wound fluids were investigated, and the expression of MMP3 protein in DPSCs was determined by immunohistochemistry staining. Meanwhile, animal models were repruduced with cutaneous incision and suturing, and the animals were respectively assigned to intractable wound group, in which rats received whole body irradiation, and simple wound group, in which no irradiation was given. The rats were sacrificed on 3rd, 5th, 7th, 10th and 14th day posttrauma （n=5 each）, and specimens of wound tissue were harvested, fixed with 10% formalin solution. Twenty four hours later, the samples were dehydrated and embeded, then paraffin section were made. Paraffin sections were stained with hematoxylin and eosin （HE） staining. Light microscopy was used to observe the pathological changes in wounds. Five randomly selected fields were observed under a X 40 objective to evaluate the histological features, especially the amount of tissue repairing cells in wounds. Furthermore, MMP3 contents in wound sites were determined by immunohistochemistry assay and image analysis. Results The expres- sion of MMP3 in DPSCs increased significantly after stimulation by wound fluids. MMP3 contents in rats of simple wound group increased significantly, especially in the dermal tissues, and the peak value appeared 5--7 days after trauma. MMP3 contents in rats of intractable wound group were significantly less than those of simple wound group, and the time when the peak value appeared was also delayed till the 10th day after trauma. Conelmions MMP3 may be an important substrate involved in wound healing. DPSCs may partidpate in the processes of wound repairing via high expre