全阴囊Ⅲ度烧伤不同方式重建阴囊对生精功能的晚期影响的实验研究

目的:探讨全阴囊Ⅲ度烧伤不同方式重建阴囊对睾丸生精细胞凋亡及bcl-2蛋白表达的影响。方法:以2月龄贵州小型猪为实验动物,雄性40只,雌性24只。雄性随机分正常对照组(Ⅰ),自然愈合组(Ⅱ),植皮组(Ⅲ),皮瓣组(Ⅳ),每组10只。建模10月末雄性对照组及实验组每组6只与同期饲养的雌猪一一配对饲养,配对3周后雌猪继续喂养4个月观察生育情况,雄猪1年末取各组双侧睾丸标本,原位末端标记法(TUNEL)检测睾丸生精细胞凋亡指数(AI),免疫组化(SABC法)检测bcl-2蛋白表达。对数据行单因素方差分析。结果:细胞凋亡结果:Ⅰ、Ⅱ、Ⅲ、Ⅳ的AI值(x±s)%分别为:7.07±3.50、40.34±4.85、15.14±1.36、39.29±5.73,Ⅰ与Ⅱ、Ⅲ、Ⅳ相比差异均有显著性(P<0.05),Ⅱ与Ⅳ相比差异无显著性(P>0.05),Ⅲ与Ⅱ、Ⅳ相比差异均有显著性(P<0.05)。bcl-2蛋白表达结果:Ⅰ、Ⅱ、Ⅲ、Ⅳ的bcl-2蛋白表达(x±s)%分别为:75.07±3.74、54.93±4.03、66.85±3.06、53.33±5.22,Ⅰ与Ⅱ、Ⅲ、Ⅳ相比差异均有显著性(P<0.05),Ⅱ与Ⅳ相比差异无显著性(P>0.05),Ⅲ与Ⅱ、Ⅳ相比差异均有显著性(P<0.05)。配对喂养结果:Ⅱ、Ⅳ组配种没有成功,Ⅰ组全部配对成功,生育幼猪(10.0±1.18)头,Ⅲ组4头配种成功,生育(9.92±1.31)头,Ⅰ组与Ⅱ、Ⅲ、Ⅳ组相比差异均有显著性(P<0.05),Ⅲ组与Ⅱ、Ⅳ组相比差异均有显著性(P<0.05),Ⅱ与Ⅳ组相比差异无显著性(P>0.05)。结论:全阴囊Ⅲ度烧伤不同方式重建阴囊1年后对生精功能均有抑制作用,导致生精细胞凋亡增加,bcl-2蛋白表达降低,其中植皮重建阴囊对睾丸生精功能影响最小,建议阴囊Ⅲ度烧伤创面采用植皮修复。

Impact of the reconstruction of the scrotum with third-degree burns on spermatogenic function: experimental study of three different methods

Objective: To explore the effects of different methods of scrotal reconstruction on the apoptosis of spermatogenic cells and expression of the bcl-2 protein in patients with third-degree scrotal burns.Methods: Forty male and 24 female 2-month-old Guizhou mini-pigs were used in this study,the former equally randomized to groups Ⅰ(normal control),Ⅱ(natural healing),Ⅲ(skin grafting) and Ⅳ(skin flap grafting).Ten months after the establishment of the model of third-degree burns,6 male pigs from each group were paired with the female pigs and fed for 3 weeks.Then the female pigs were fed for another 4 months,followed by observation of their reproductivity.At 12 months,the bilateral testes were taken from the male pigs for detection of the apoptosis index of spermatogenic cells by TUNEL and determination of the expression of the bcl-2 protein by immunohistochemistry.The data obtained were subjected to single factor analysis of variance.Results: The apoptosis indexes of spermatogenic cells were(7.07±3.5),(40.34±4.85),(15.14±1.36) and(39.29±5.73)% in groups Ⅰ,Ⅱ,Ⅲ and Ⅳ,respectively,significantly higher in groups Ⅱ,Ⅲ and Ⅳ than in Ⅰ(P<0.05),with statistically significant differences between group Ⅲ and groups Ⅱ and Ⅳ(P<0.05) but not between Ⅱ and Ⅳ(P>0.05).The expression rates of the bcl-2 protein were(75.07±3.74),(54.93±4.03),(66.85±3.06) and(53.33±5.22)% in groups Ⅰ,Ⅱ,Ⅲ and Ⅳ,respectively,remarkably higher in Ⅰ than in the other three(P<0.05),with significant differences between group Ⅲ and groups Ⅱ and Ⅳ(P<0.05) but not between Ⅱ and Ⅳ(P>0.05).Pregnancies were found in all the female pigs of group Ⅰ with 10.0±1.18 newborns and in 4 of group Ⅲ with 9.92±1.31 newborns,but in none of groups Ⅱ and Ⅳ,with significant differences between group Ⅰ and the other three(P<0.05) as well as between group Ⅲ and groups Ⅱ and Ⅳ(P<0.05),but not between Ⅱ and Ⅳ(P >0.05).Conclusion: All the three methods of reconstruction for the scrotum with third-degree burns can suppress spermatogenic function,increase the apoptosis of spermatogenic cells and decrease the expression of the bcl-2 protein,among which,skin grafting least affects spermatogenic function.