摘要目的 探讨重组人角质细胞生长因子2(rhKGF-2)对重度烟雾吸入性损伤兔肺组织的作用. 方法 将120只新西兰大白兔制成重度烟雾吸入性损伤模型后,采用随机数字表法分成5组,每组24只.单纯损伤组兔吸入空气;损伤+磷酸盐缓冲液(PBS)组兔每日雾化吸入PBS 5 mL,每日1次,连续7d;损伤+1 mg/kg rhKGF-2组、损伤+2mg/kg rhKGF-2组、损伤+5mg/kg rhKGF-2组兔分别每日雾化吸入1、2、5 mg/kg的rhKGF-2(均溶入5 mL PBS中),每日1次,连续7d.治疗1、3、5、7d,各组分别取6只兔,取耳中央动脉血,抽血后处死兔,取兔气管隆突处组织和肺.手持式血液分析仪检测血pH值、动脉血氧分压(PaO2)、动脉血二氧化碳分压(PaCO2)和碳酸氢根离子,蛋白质印迹法检测肺组织中肺表面活性物质相关蛋白质A(SP-A)和血管内皮生长因子(VEGF)的表达,苏木素-伊红素染色观察肺组织和气管病理形态.对数据行两因素析因设计方差分析、Tukey检验.结果 (1)与单纯损伤组比较,其余各组兔治疗1～7d血pH值无明显变化(P＞0.05).损伤+2 mg/kg rhKGF-2组兔治疗5、7d PaO2分别为(75.0±2.4)、(71.0±4.5) mmHg(1 mmHg=0.133 kPa),均较单纯损伤组的(62.0±6.8)、(63.0±3.0) mmHg明显升高(q=4.265、8.202,P＜0 05或P ＜0.01);损伤+5mg/kg rhKGF-2组兔治疗7 d PaO2为(82.0±4.9)mmHg,较单纯损伤组明显升高(q =6.234,P＜0.01).与单纯损伤组比较,损伤+2mg/kg rhKGF-2组兔治疗3 d PaCO2明显降低(q =4.876,P＜0.01),治疗5 d PaCO2明显升高(q=5.562,P＜0.01);损伤+5 mg/kgrhKGF-2组兔治疗5、7 d PaCO2明显升高(q=5.013、4.601,P＜0.05或P＜0.01).与单纯损伤组比较,损伤+1 mg/kg rhKGF-2组兔治疗7d血碳酸氢根离子明显升高(q=5.142,P＜0.01),损伤+2 mg/kg rhKGF-2组兔治疗5、7d血碳酸氢根离子明显升高(q=4.830、6.934,P＜0.01),损伤+5 mg/kg rhKGF-2组兔治疗5d血碳酸氢根离子明显升高(q=3.973,P＜0.05).(2)损伤+PBS组兔治疗各时间点肺组织中SP-A表达量与单纯损伤组相近(P＞0.05).损伤+2 mg/kg rhKGF-2组、损伤+5 mg/kg rhKGF-2组兔治疗3d肺组织中SP-A表达量分别为0.091±0.007、0.101 ±0.009,较单纯损伤组的0.069±0.009明显升高(q=10.800、13.580,P＜0.01).损伤+1 mg/kg rhKGF-2组、损伤+2 mg/kg rhKGF-2组、损伤+5mg/kg rhKGF-2组兔治疗5、7d,肺组织中SP-A表达量分别为0.127 ±0.008、0.132 ±0.006、0.194±0.006及0.152±0.017、0.166±0.004、0.240±0.008,较单纯损伤组的0.092±0.003、0.108 ±0.005明显升高(q=6.789、12.340、17.900、9.875、31.480、40.740,P＜0.01).(3)治疗1、5d,各组兔肺组织中VEGF表达量无明显差异(P＞0.05).与单纯损伤组比较,损伤+2 mg/kg rhKGF-2组兔治疗3、7 d肺组织中VEGF表达量明显升高(q=4.243、8.000,P ＜0.05或P＜0.01),损伤+5 mg/kg rhKGF-2组兔治疗7d肺组织中VEGF表达量明显升高(q=20.720,P＜0.01).(4)治疗1d,各组兔损伤情况相似,肺泡腔内及间质内大量中性粒细胞浸润伴脓肿形成,肺泡间隔增厚,部分肺泡萎陷、肺不张;气管黏膜大片变性、坏死,腔内大量炎性渗出物阻塞.治疗3d,各组兔肺组织及气管炎症有所改善,但单纯损伤组与损伤+PBS组仍较为严重.治疗5 d,损伤+2 mg/kg rhKGF-2组及损伤+5 mg/kg rhKGF-2组兔肺组织及气管炎症改善较其他组更为明显.治疗7d,损伤+5 mg/kg rhKGF-2组兔肺组织炎症较其他组明显减轻,大部分肺泡未见明显渗出液,肺泡结构完整,肺泡腔清晰,局部肺泡囊状扩张、肺泡间隔变薄;气管炎症反应较其他组改善也更为明显,气管黏膜更趋于完整,腔内零星中性粒细胞浸润. 结论 雾化吸入rhKGF-2可以提高重度烟雾吸入性损伤兔PaO2水平,减少气道炎症反应,增加肺组织中SP-A及VEGF表达,从而促进肺组织修复.

abstractsObjective To investigate the effect of recombinant human keratinocyte growth factor 2 (rhKGF-2) on lung tissue of rabbits with severe smoke inhalation injury.Methods A total of 120 New Zealand rabbits were divided into 5 groups by random number table after being inflicted with severe smoke inhalation injury,with 24 rats in each group.Rabbits in the simple injury group inhaled air,while rabbits in the injury + phosphate buffer solution (PBS) group inhaled 5 mL PBS once daily for 7 d.Rabbits in injury + 1 mg/kg rhKGF-2 group,injury + 2 mg/kg rhKGF-2 group,and injury + 5 mg/kg rhKGF-2 group received aerosol inhalation of 1 mg/kg,2 mg/kg,and 5 mg/kg rhKGF-2 (all dissolved in 5 mL PBS) once daily for 7 d,respectively.On treatment day 1,3,5,and 7,blood samples were taken from the ear central artery of 6 rabbits in each group.After the blood was taken,the rabbits were sacrificed,and the tracheal carina tissue and lung were collected.Blood pH value,arterial oxygen partial pressure (PaO2),arterial blood carbon di-oxide pressure (PaCO2),and bicarbonate ion were detected by handheld blood analyzer.The expressions of pulmonary surfactant-associated protein A (SP-A) and vascular endothelial growth factor (VEGF) in lung tissue were detected by Western blotting.Pathomorphology of lung tissue and trachea was observed by hematoxylin-eosin staining.Data were processed with analysis of variance of two-way factorial design and Tukey test.Results (1) Compared with those in simple injury group,the blood pH values of rabbits in the latter groups on treatment day 1-7 had no obvious change (P ＞ 0.05).The PaO2 of rabbits in injury + 2 mg/kg rhKGF-2 group on treatment day 5 and 7 were (75.0 ± 2.4) and (71.0 ± 4.5) mmHg (1 mmHg =0.133 kPa),respectively,which were significantly higher than (62.0 ± 6.8) and (63.0 ±3.0) mmHgin simple injury group (q =4.265,8.202,P ＜0.05 orP ＜0.01).The PaO2 of rabbits in injury + 5 mg/kg rhKGF-2 group on treatment day 7 was (82.0 ± 4.9) mmHg,which was significantly high-er than that in simple injury group (q =6.234,P ＜ 0.01).Compared with that in simple injury group,the PaCO2 of rabbits in injury + 2 mg/kg rhKGF-2 group on treatment day 3 was significantly decreased (q =4.876,P ＜0.01) and significantly increased on treatment day 5 (q =5.562,P ＜0.01);the PaCO2 of rabbits in injury + 5 mg/kg rhKGF-2 group was significantly increased on treatment day 5 and 7 (q =5.013,4.601,P ＜ 0.05 or P ＜ 0.01).Compared with that in simple injury group,the serum bicarbonate ion of rabbits in injury + 1 mg/kg rhKGF-2 group on treatment day 7 was significantly increased (q =5.142,P ＜0.01);the serum bicarbonate ion of rabbits in injury + 2 mg/kg rhKGF-2 group on treatment day 5 and 7 were significantly increased (q =4.830,6.934,P ＜ 0.01);the serum bicarbonate ion of rabbits in injury + 5 mg/kg rhKGF-2 group on treatment day 5 were significantly increased (q =3.973,P ＜0.05).(2) The expressions of SP-A in lung tissue of rabbits in simple injury group and injury + PBS group in each treatment time point were close (P ＞ 0.05).The expressions of SP-A in lung tissue of rabbits in injury + 2 mg/kg rhKGF-2 group and injury + 5 mg/kg rhKGF-2 group on treatment day 3 were 0.091 ± 0.007 and 0.101 ± 0.009,respectively,significantly higher than 0.069 ± 0.009 in simple injury group (q =10.800,13.580,P ＜ 0.01).The expressions of SP-A in lung tissue of rabbits in injury + 1 mg/kg rhKGF-2 group,injury + 2 mg/kg rhKGF-2 group,and injury + 5 mg/kg rhKGF-2 group on treatment day 5 and 7 were 0.127 ±0.008,0.132 ±0.006,0.194 ±0.006,0.152 ±0.017,0.166 ±0.004,0.240 ±0.008,significantly higher than 0.092 ± 0.003 and 0.108 ± 0.005 in simple injury group (q =6.789,12.340,17.900,9.875,31.480,40.740,P ＜0.01).(3) On treatment day 1 and 5,there was no significant difference in the expression of VEGF in lung tissue of rabbits among the 5 groups (P ＞ 0.05).Compared with those in simple injury group,the expressions of VEGF in lung tissue of rabbits in injury +2 mg/kg rhKGF-2 group on treatment day 3 and 7 were significantly increased (q =4.243,8.000,P ＜0.05or P ＜ 0.01),and the expression of VEGF in lung tissue of rabbits in injury + 5 mg/kg rhKGF-2 group on treatment day 7 was significantly increased (q =20.720,P ＜ 0.01).(4) On treatment day 1,the injury of rabbits in each group was similar,with a large number of neutrophils infiltrated and abscess formed in the alveolar and interstitial tissue,thickened alveolar septum,some collapsed alveolar and atelectasis;large area of tracheal mucosa was degenerated and necrotic,with a large amount of inflammatory exudates blocking in the cavity.On treatment day 3,the inflammation of lung tissue and trachea in each group were improved,but the inflammation in simple injury group and injury + PBS group was also serious.On treatment day 5,the inflammation in lung tissue and trachea of rabbits in injury + 2 mg/kg rhKGF-2 group and injury +5 mg/kg rhKGF-2 group were improved much obviously than those in the other groups.On treatment day 7,the inflammation in lung tissue of rabbits in injury + 5 mg/kg rhKGF-2 group alleviated obviously than those in the other groups,most alveoli had no obvious exudative fluid,the alveolar cavity was intact and clear,the local alveolar dilated like a cyst,and the alveolar septum thinning;the improvement of inflammation of trachea was more obvious than the other groups,the tracheal mucosa tended to be more complete,and few neutrophils were infiltrated in the endotracheal cavity.Conclusions Atomization inhalation of rhKGF-2 can improve the PaO2 level of rabbits with severe smoke inhalation injury,reduce airway inflammation,increase the expression of SP-A and VEGF in lung tissue,thus promoting the repair of lung tissue.