论文部分内容阅读
目的:探讨降钙素基因相关肽(CGRP),对内毒素急性肺损伤(ALI)的保护作用。方法:应用内毒素(LPS,6mg/kg,iv)复制大鼠ALI模型。选用SD大鼠24只,随机分成盐水对照组(Ns.n=8)、ALI模型组(LPS,n=8)、CGRP干预组(n=8)CGRP干预组按2μg/kg经腹腔注入CGRP,30min后再经颈静脉注入LPS;LPS组以生理盐水代替CGRP;NS组中、CGRP和LPS均以等量生理盐水代替。各组大鼠均于注射LPS或生理盐水6h后测定动脉血氧分压(PaO_2)、血清肿瘤坏死因子(TNF-α)及白介素-8(IL-8)含量,随后处死动物,观察肺病理改变,测定肺湿/干重比(W/D)及肺组织匀浆髓过氧化物酶(MPO)浓度。结果:注射LPS 6h后,W/D、肺组织匀浆MPO、血清TNF-α、IL-8含量较对照组均有显著升高(P<0.01)、PaO_2显著降低;而预先给予CGRP(2μg/kg)干预可显著缓解上述变化,PaO_2改善.MPO含量较ALI模型组降低(P<0.05),肺组织病理改变明显减轻。结论:小剂量CGRP能改善大鼠ALI时气体交换功能,抑制炎症介质的释放,对内毒素诱导的ALI有保护作用。
Objective: To investigate the protective effect of calcitonin gene related peptide (CGRP) on acute lung injury induced by endotoxin (ALI). Methods: Rat ALI model was induced by LPS (6mg / kg, iv). Twenty-four SD rats were randomly divided into saline control group (Ns.n = 8), ALI model group (LPS, n = 8) and CGRP intervention group (n = 8) , And then injected into LPS via jugular vein 30min later. LPS group was replaced by saline instead of CGRP. In NS group, CGRP and LPS were replaced by normal saline. PaO2, serum TNF-alpha and IL-8 levels were determined in rats of each group after LPS or saline injection for 6h. Animals were then sacrificed to observe pulmonary pathology Changes in lung wet / dry weight ratio (W / D) and lung tissue homogenate myeloperoxidase (MPO) concentrations. Results: Compared with control group, W / D, MPO, TNF-α and IL-8 in lung homogenate were significantly increased (P <0.01) and PaO_2 decreased significantly / kg) could significantly ameliorate the above changes, and PaO_2 could be improved.MPO content was lower than that of ALI model group (P <0.05), and the pathological changes of lung tissue were obviously alleviated. CONCLUSION: Low dose CGRP can improve gas exchange function, inhibit the release of inflammatory mediators and protect endotoxin-induced ALI in rats.