本实验通过建立大鼠皮肤创面模型，研究多聚合复糖医用胶液材料(MCPGL)在动物创面愈合过程中的作用及机制。

选取Wistar大鼠20只，于每只大鼠背部脊柱旁两侧制备4个相同大小的圆形创面，直径均为1.5 cm，并将每只大鼠4个创面依据给药方法分组：模型组(伤后不给药)、透明质酸钠组(给予透明质酸钠溶液)、MCPGL低剂量组(给予MCPGL 200 μL)及MCPGL高剂量组(给予MCPGL 300 μL)，每组20个创面。伤后首次给药后每天固定时间分别在其患处给药2次，连续给药至伤后第21天。观察大鼠创面愈合情况，记录并计算大鼠创面愈合时间和愈合速率；取创面皮肤组织，利用RT-PCR检测相关细胞生长因子胰岛素样生长因子(IGF)、血管内皮生长因子(VEGF)的mRNA表达量；创面皮肤组织固定后经苏木精-伊红(HE)染色，观察伤口局部组织病理学变化。对数据进行单因素方差分析和SNK检验。

伤后当天各创面患处深达筋膜层，部分创面渗血；伤后第3天MCPGL低剂量组、MCPGL高剂量组创面收缩，并且MCPGL高剂量组出现结痂；伤后第7天，各组创面出现不同程度肉芽组织增生，其中MCPGL高剂量组尤为显著；伤后第14、21天各组创面均基本上皮化。伤后第3天，4组间创面愈合速率比较差异有统计学意义(F＝8.336，P<0.05)；与模型组相比，MCPGL高剂量组创面愈合速率显著加快，差异有统计学意义(P<0.05)。伤后第7天，4组间创面愈合速率比较差异有统计学意义(F＝33.569，P<0.05)；与模型组(48.9±13.5)%相比，透明质酸钠组、MCPGL高剂量组愈合速率(71.4±10.8)、(75.4±4.8)%均显著加快，差异均有统计学意义(P值均小于0.05)。伤后第14天，4组间创面愈合速率比较差异有统计学意义(F＝9.885，P<0.05)；与模型组相比，MCPGL高剂量组创面愈合速率显著加快，差异有统计学意义(P<0.05)。伤后第21天，4组间创面愈合速率比较差异无统计学意义(F＝2.455，P＝0.07)；与模型组相比，其他3组差异均无统计学意义(P值均大于0.05)。4组间创面愈合时间比较差异无统计学意义(F＝1.531，P＝0.228)。MCPGL高剂量组愈合时间(18.2±3.2) d，与模型组、透明质酸钠组(20.9±2.3)、(20.5±4.0)d相比，差异均无统计学意义(P值均大于0.05)；MCPGL低剂量组创面愈合时间为(20.7±1.3)d，与模型组、透明质酸钠组比较，差异均无统计学意义(P值均大于0.05)。伤后第7天，4组间IGF的mRNA表达量比较差异有统计学意义(F＝130.925，P<0.05)；与模型组0.73±0.04比较，MCPGL低剂量组和MCPGL高剂量组的IGF的mRNA表达量1.04±0.09、1.08±0.03均增高，差异均有统计学意义(P值均小于0.05)。伤后第7天，4组间VEGF的mRNA表达量比较差异有统计学意义(F＝84.976，P<0.05)；与模型组0.93±0.06比较，MCPGL低剂量组和MCPGL高剂量VEGF的mRNA表达含量1.23±0.03、1.14±0.08均增高，差异均有统计学意义(P值均小于0.05)。伤后第7天，大鼠创面组织病理观察，模型组中肉芽组织数量较少，成纤维细胞排列散乱，内含大量炎性细胞，无完整表皮覆盖创面；与模型组对比，MCPGL低剂量组肉芽组织已填满整个创面区域、表皮已完全覆盖伤口表面，内含较多的炎性细胞浸润；MCPGL高剂量组成纤维细胞数量较多，形成了大量新生肉芽组织，并伴有新生毛细血管生成，表皮完全覆盖伤口表面，有少量炎性细胞浸润。

结果表明，在伤后14 d内，MCPGL可加速伤口愈合，MCPGL明确具有促进创面愈合的作用。推测其作用机制为MCPGL通过促进相关生长因子的表达从而促进创面愈合。

To investigate the effect of medical complex polysaccharides gel liquid(MCPGL) and its mechanism in process of wound healing by establishing rats model of skin wound.

Twenty Wistar rats, a total of 80 wounds were prepared. Four circular wounds of the same size were prepared on both sides of the spine in each rat, and the diameter of each wound was 1.5 cm. The experiment was randomly divided into 4 groups: model group(no treatment after injury), positive drug group (sodium hyaluronate), MCPGL low dose group (MCPGL 200 μL) and MCPGL high dose group (MCPGL 300 μL), each group had 20 wounds. After the operation, the medicine was administered twice a day in the affected area till the 21st d. The rat wound healing time and healing rate were observed after injury. The expression level of cell growth factors [insulin-like growth factor (IGF), vascular endothelial growth factor (VEGF)] were detected by RT-PCR. Pathological changes were observed in the local wound pathology by hematoxylin and eeosin (HE) staining. Single factor analysis of variance and t test were used for the study.

At the day of injury, the wound deeply affected to fascia layer; 3rd d after injury, wounds of MCPGL low dose group and MCPGL high dose group were contracted, and MCPGL high dose group showed scab; 7th d after injury, wound granulation tissue appeared on several levels, the high dose of MCPGL group was particularly significant; 14th d and 21st d after injury, the 4 groups all appeared wound epithelization. At the 3rd d after injury, the rate of healing was statistically significant difference among the 4 groups (F=8.336, P<0.05). Compared with the model group, MCPGL high dose group significantly accelerated the wound healing rate (P<0.05); the 7th d after injury, the rate of healing was statistically significant difference among the 4 groups (F=33.569, P<0.05). Compared with the model group (48.9±13.5)%, the wound healing rate of sodium hyaluronate group and MCPGL high dose group were (71.4±10.8)%, (75.4±4.8)%, there were significant differences (with P values below 0.05); the 14th d after injury, the healing rate was statistically significant difference among the 4 groups (F=9.885, P<0.05). Compared with the model group, MCPGL high dose group significantly accelerated wound healing rate (P<0.05); the 21st d after injury, the rate of healing was not statistically significant difference among the 4 groups (F=2.45, P=0.07), compared with the model group, the other 3 groups had no statistically significant difference ( with P values above 0.05). The time of healing was not statistically significant difference among the 4 groups (F=1.531, P=0.228). Compared with the model group, sodium hyaluronate group (20.9±2.3) d, (20.5±4.0) d, MCPGL high dose group (18.2±3.2)d, the difference was not statistically significant (with P values above 0.05); compared with the model group, sodium hyaluronate group, MCPGL low dose group (20.7±1.3)d, the differences were not statistically significant (with P values above 0.05). At the 7th d after injury, the expression of IGF was statistically significant difference among the 4 groups (F=130.925, P<0.05). Compared with the model group 0.73±0.04, the expression of IGF mRNA in the MCPGL low dose group 1.04±0.09 and MCPGL high dose group 1.08±0.03 both increased, the differences were statistically significant (with P values below 0.05). Seventh day after injury, the expression of VEGF mRNA was statistically significant difference among the 4 groups (F=84.976, P<0.05). Compared with the model group 0.93±0.06, the expression levels of VEGF mRNA in MCPGL low dose group 1.23±0.03 and MCPGL high dose 1.14±0.08 increased, the differences were statistically significant (with P values below 0.05). The 7th d after injury had pathological observation of wound tissue in rats. In the model group, small number of fibroblasts arranged scattered, containing a large number of inflammatory cells, without complete epidermis covered the wound skin; compared with the model group, MCPGL low dose group of granulation tissue had filled in the wound area, skin had completely covered the surface of the wound. Containing more inflammatory cell infiltration; MCPGL high dose consisted more fiber cells, formed a large number of granulation tissue, and accompanied by newborn capillaries. Epidermis covered the wound surface completely, and there was a small amount of inflammatory cell infiltration.

The results show that MCPGL can accelerate wound healing within 14 d after injury, and MCPGL has the effect of promoting wound healing. Then the mechanism of action for MCPGL promoting wound healing by promoting the expression of related growth factors can be presumed.