芦荟提取物对大鼠烫伤创面微血管形成的影响

Formation of tissue microvessels in burned rats in response to aloe extracts

目的 探讨芦荟提取物对大鼠烫伤创面修复过程中微血管形成的影响。方法Wistar大鼠48只，随机分为8组，每组6只。每只背部造成4处直径3cm深Ⅱ度烫伤创面，分别外涂质量分数分别为5％、10％、1％的芦荟粗多糖膏、芦荟凝胶膏、磺胺嘧啶银（SD-Ag）霜等渗盐水作空白对照，测量和计算烫伤后第10，14，18，21天创面面积，计算创面愈合率，并于烫伤前、伤后4h、12h、24h、48h和7d、14d、21d分别取大鼠创面皮肤测定创面组织中血管内皮生长因子（VEGF）含量，采用Ⅷ因子免疫组织化学染色计算微血管密度（MVD）。结果 5％芦荟粗多糖组和10％芦荟凝胶组（简称前者）与SD-Ag霜组和等渗盐水组（简称后者）相比，烫伤后14，18，21d，前者创面愈合率显著大于后者（P〈0．05）；烫伤后48h、7d、14d和21d，前者比后者创面VEGF含量显著增加（P〈0.05）；在烫伤后14d和21d，前者创面微血管密度显著大于后者（P〈0．05）；而5％芦荟粗多糖组与10％芦荟凝胶组间、SD-Ag霜组与等渗盐水组间比较，差异无统计学意义。结论 芦荟粗多糖和芦荟凝胶能通过增加烫伤创面组织VEGF的合成与释放，增加创面的微血管形成，促进创面愈合。

Objective To investigate the effects of gel and coarse polysaccharide extracted from aloe barbadensis on tissue microvascular formation in burned rats. Methods Forty-eight male Wistar rats were randomly divided into eight groups （ six rats in each group）, eachof which was given four deep degree Ⅱ burn wound with 3 cm in diameter on the back. After 5% aloe coarse polysaccharide, 10% aloe vera gel, 1% sulfanilamide pyridine silver （SD-Ag） cream, isotonic saline solution were applied on each wound, respectively, the burned area was measured at days 10, 14, 18 and 21 and wound healing rate counted. Vascular endothelial growth factor （VEGF） level in wound tissues was detected at 4, 12, 24 and 48 hours and 7, 14 and 21 days before and after burn, when microvascular density （MVD） was measured by means of gene Ⅷ immunohistochemistry. Results At 14, 18 and 21 days after burn, the wound healing area in 5% aloe coarse polysaccharide group and 10% aloe vera gel group was larger significantly than that in SD - Ag group and isotonic saline solution group （ P 〈 0.05）. At 48 hours, 7, 14 and 21 days after burn, VEGF level in wounds tissues of 5% aloe coarse polysaccharide group and 10% aloe vera gel group was more significantly higher than that in SD-Ag group and isotonic saline solution group （P 〈0.05）. At 14 and 21 days after burn, MVD of wounds tissue in 5% aloe coarse polysaccharide group and 10% aloe vera gel group was significantly higher than that in SD -Ag group and isotonic saline solution group （P 〈0.05）. There was no significant difference between 5% aloe coarse polysaccharide group and 10% aloe gel group, and between SD-Ag group and isotonic saline solution group. Conclusion Both aloe coarse polysaccharide and aloe gel can accelerate tissue microvascular formation and wound healing by increasing synthesis and release of VEGF.