重组人生长激素对败血症大鼠急性肺损伤的治疗及其机制

目的　观察重组人生长激素(rhGH)对败血症大鼠急性肺损伤(ALI)的治疗效果并探讨其作用机制。方法　采用鸵鸟株E .coli复制败血症大鼠ALI模型。观测对照组、ALI组及rhGH治疗组大鼠的肺组织病理评分、支气管肺泡灌洗液(BALF)中NO水平及肺组织诱生型一氧化氮合酶(iNOS)蛋白的表达情况。结果　ALI组大鼠肺组织病理评分、BALF中NO水平及肺组织iNOS蛋白表达水平明显高于对照组,且NO与iNOS蛋白表达水平呈明显正相关。rhGH能明显降低败血症大鼠BALF中NO及肺组织iNOS水平,减轻肺损伤程度。结论　由iNOS诱导产生的过量NO可促进败血症大鼠ALI的发生;rhGH对败血症大鼠ALI具有较理想的治疗效果,其机制可能与rhGH通过影响iNOS表达来降低肺组织NO水平等有关。

Therapeutic effect of recombinant human growth hormone on rat acute lung injury caused by sepsis and its mechanisms

OBJECTIVE To investigate therapeutic effect of recombinant human growth hormone (rhGH) on rat acute lung injury(ALI) caused by sepsis and its possible mechanisms. METHODS E. coli was injected intraperitoneally to prepare ALI models. Histopathological scoring of lung tissue, nitric oxide(NO) content in bronchial alveolar lavage fluid(BALF) and expressions of inducible nitric oxide synthase(iNOS) in lung tissue were determined among control group, ALI group and rhGH group. RESULTS Histopathological scoring of lung tissue, NO content in BALF and expressions of iNOS in lung tissue in ALI group were obviously higher than that in control group, and NO content had a positive correlation with iNOS expressions. rhGH could significantly decrease iNOS expressions and NO content in BALF ,and alleviate lung injuries. CONCLUSION Excessive NO mediated by iNOS may aggravate ALI. rhGH showes desirable beneficial effects on rat ALI caused by sepsis, which may attribute to its influencing iNOS expressions and diminish NO content in lung tissue.