间断及持续缺氧扩张条件下大鼠真皮层组织重构特点的研究

Study on the characteristics of dermis after remodeling in rats under persistent and intermittent hypoxia-controlled tissue expansion

目的探究皮肤软组织扩张过程中,间断缺氧(intermittent hypoxia,IH)及持续缺氧(persistent hypoxia,PH)扩张后真皮层组织学变化。方法自2016年11月至2017年6月,空军军医大学西京医院整形外科对大鼠间断及持续缺氧扩张后皮肤标本行HE及Masson染色,观察真皮层结构和胶原含量变化;增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)及末端脱氧核苷酸转移酶介导的dUTP缺口末端标记测定法(terminal-deoxynucleotidyl transferase mediated nick end labeling,TUNEL)测定真皮成纤维细胞增殖及凋亡情况;CD31染色分析真皮层血管形态及密度变化。结果IH组真皮厚度为(500.20±22.57)μm,PH组为(464.30±27.23)μm,正常皮肤组为(759.40±27.23)μm,PH组较IH组明显变薄,差异有统计学意义(P<0.05)。IH组及PH较正常皮肤组胶原含量增高,且IH组较PH组增高明显,差异有统计学意义(P<0.05)。正常皮肤组真皮层PCNA阳性成纤维细胞密度为6.10个/高倍视野,IH组为19.38个/高倍视野,PH组为15.82个/高倍视野,IH组阳性细胞计数较PH组高,两组比较差异有统计学意义(P<0.05)。正常皮肤组真皮层TUNEL阳性成纤维细胞为5.10个/高倍视野,IH组为16.05个/高倍视野,PH组为13.05个/高倍视野。IH组TUNEL阳性成纤维细胞密度较PH组升高,但两组比较差异无统计学意义(P>0.05)。IH组真皮层每高倍视野毛细血管平均为(22.87±1.13)个,PH组为(13.57±0.43)个,两组数值差异有统计学意义(P<0.05)。结论IH扩张能更有效地刺激真皮成纤维细胞增殖、减少细胞凋亡、促进胶原合成及真皮血管网的重构,更有利于扩张皮肤的生物性生长。

Objective To explore the dermal histological changes of rat expanded skin under persistent tissue hypoxic expansion and intermittent tissue hypoxic expansion.Methods From November 2016 to June 2017,a rat model was used in the Plastic Surgery Department of Xijing Hospital of the Air Force Medical University.After intermittent and continuous hypoxic tissue expansion,the skin samples of rats were stained with HE and Masson staining to observe the changes in the structure and collagen content of the dermis;Proliferating cell nuclear antigen(PCNA)and Terminal-deoxynucleotidyl transferase mediated nick end labeling(TUNEL)staining were used to determine the proliferation and apoptosis of dermal fibroblasts;CD31 staining was used to analyze the changes of vascular morphology and capillary density in the dermis.Results The dermal thicknesses in the IH group,PH group,and the normal group were(500.20±22.57)μm.(464.30±27.23)μm,and(759.40±27.23)μm respectively.The dermal thickness of the PH group was significantly smaller than the IH group(P0.05).The collagen content in the IH group and PH group was significantly higher than that in the normal skin group(P0.05).The densities of PCNA-positive fibroblasts in the dermis of the normal skin group,IH group,and PH group were 6.10 per high power field,19.38 per high power field,and 15.82 per high power field respectively.The number of positive cells in the IH group was higher than that in the PH group(P0.05).The number of TUNEL-positive fibroblasts in the dermis of the normal skin group,IH group,and PH group was5.10 per high-power field,16.05 per high-power field,and 13.05 per high-power field.The density of TUNEL-positive fibroblasts in the IH group was higher than that in the PH group,but no statistically significant difference was found between the two groups(P0.05).The average numbers of capillaries per high-power visual field in the dermis of the IH group and PH group were 22.87±1.13 and 13.57±0.43,a statistically significant difference was found between the two groups(P0.05).Conclusion Intermittent hypoxic tissue expansion can more effectively stimulate the proliferation of dermal fibroblasts,reduce cell apoptosis,promote collagen synthesis,and reconstruct the dermal vascular network,which is more conducive to the biological growth of the expanded skin.