TNF-α和PDGF在保存羊膜移植治疗兔角膜急性碱烧伤中的作用

Effect of TNF-α and PDGF in preserved amniotic membrane transplantation at early stage of acute corneal alkali burn in rabbits

目的:观察保存羊膜移植治疗兔角膜急性碱烧伤眼的组织学变化并探讨肿瘤坏死因子α(tumor necrosis factor α,TNF-α)和血小板源性生长因子(platelet derived growth factor,PDGF)的作用。方法:建立兔急性角膜碱烧伤模型,并于24h内行保存羊膜移植术(右眼,12眼/组),设左眼为对照组。术后观察双眼形态及角膜新生血管变化,并检测房水中TNF-α含量及角膜组织PDGF-BB的表达情况。结果:与对照组比较,治疗组炎症反应轻,角膜溃疡范围小,上皮再生速度快,新生血管长度短(P<0.05)。7,28d治疗组房水TNF-α含量分别为315.5±19.8ng/L和140.6±11.5ng/L,明显低于对照眼的363.0±28.5ng/L和283.5±19.9ng/L(P<0.05)。与对照组比较,治疗组PDGF蛋白表达升高(P<0.05)。结论:角膜急性碱烧伤后早期行保存羊膜移植术,能抑制眼内炎症,促进角膜修复,其作用与抑制TNF-α,促进PDGF表达有关。

AIM： To observe the effect of tumor necrosis factor a （TNF-α） and platelet derived growth factor （PDGF） in preserved amniotic membrane transplantation （AMT） during early corneal alkali burns in rabbits.METHODS. Twelve rabbits were used to establish corneal alkali burn models with lmmol/L sodium hydroxide and the AMT was performed within 24 hours in the right eyes, and the left eyes were as control. The morphologic change of eyes was observed regularly and the TNF-a concentration of aqueous humor was measured by enzyme linked immunosorbent assay method 7, 14, 21, 28 days after AMT procedure. Also, PDGF-BB （a maker of PDGF） protein expression of corneal tissue was observed by immunohistochemistry method. RESULTS： Compared to the control group, the AMT eyes showed moderate corneal inflammation, distinctive ulcer boundary, quick epithelium regeneration and shorter corneal neovascularization length. The TNF-α concentration in the 7th and 28th day in ATM group was 315.5 ±19. 8 ng/L and 140. 6 ± 11. 5 ng/L respectively,which was significantly lower than those in control group with 363.0± 28.5 ng/L and 283.5 ± 19.9 ng/L （ P〈 0.05）. The PDGF-BB protein expression increased 14 and 28 days after ATM procedure than those in control group （ P 〈 0.05）. CONCLUSION ;The preserved AMT is effective in ocular reconstruction in early stage of corneal alkali burns, which may resulted from the inhibition of TNF-α concentration and the increase of PDGF expression.