低氧致大鼠凝血功能异常对肺组织结构的改变及灯盏花素对其的拮抗作用

Hypoxemia Induced the Changing Structure of the Lung Tissue in SD Rat Though Changing Blood Clotting and the Effects of Breviscapine’s Intervention

中文关键词:  低氧 肺纤维化 血液凝固 灯盏花素

英文关键词:Hypoxia Pulmonary fibrosis Blood coagulation Breviscapine

中文摘要:

      目的 研究不同低氧时间作用下大鼠肺组织中纤溶酶原激活物抑制物（PAI-1）、活化蛋白酶C（APC）表达量及肺组织结构的变化及灯盏花素对上述改变的影响。方法 选取80只SD大鼠，将其随机分为：A（常氧对照）组、B（单纯低氧）组、C（低氧+低剂量灯盏花素）组、D（低氧+高剂量灯盏花素）组。各低氧组每天置于常压性低氧 (101 kPa、10%O2)环境中处理8 h,低剂量及高剂量灯盏花素组分别给予腹腔注射10 mg/kg体质量、40 mg/kg体质量的灯盏花素。于实验第3、7、14、21 d每组随机处死5只大鼠，HE染色观察肺组织病理改变，RT-PCR检测转化生长因子β1 (TGF-β1)、PAI-1的mRNA表达量,Western blot法检测PAI-1蛋白的表达量，ELISA法检测肺泡灌洗液（BALF）中APC蛋白的表达量。结果 ①HE染色提示3~21 d低氧环境下肺泡间隔有不同程度增厚。3~21 d，B组大鼠肺组织中TGF-β1、PAI-1的mRNA表达量及PAI-1蛋白表达量均较A组增高（P<0.05），BALF中APC蛋白的表达量较A组降低（P<0.05），且随着低氧时间延长，上述变化越显著。PAI-1 mRNA与TGF-β1表达水平呈正相关（r=0.913,P<0.05）。②与B组比较，C、D组21 d时肺泡间隔增厚程度减轻，TGF-β1、PAI-1的mRNA表达量及PAI-1蛋白表达量降低（P<0.05），BALF中APC蛋白的表达量增加（P<0.05），且D组变化较C组明显（P<0.05)。结论 低氧可能造成凝血功能异常，使凝血活性增高，纤溶活性及抗凝活性降低，上调PAI-1水平及下调APC水平致肺泡间隔增厚，其机制可能与TGF-β1信号通路有关。而灯盏花素可以改善低氧所致的高凝状态，减轻肺泡间隔增厚。

英文摘要:

      Objective To investigate the expressions of plasminogen activator inhibitor-1 (PAI-1), activated protein C (APC) and the histology structures of the rat lung tissues in the different hypoxia time; and to investigate the effects of breviscapine to the above changes. Methods Eighty SD rats were randomly divided into A (control), B (hypoxia), C (hypoxia+low-dose breviscapine) and D (hypoxia+high-dose breviscopine) groups with 20 rats in each group. Each hypoxia group placed daily pressure (101 kpa, 10% O2) environment for 8 h, low-dose and high-dose breviscapine groups were given of 10 mg/kg, 40 mg/kg breviscapine by intraperitoneal injection. On the 3^rd,7^th,14^th and 21^st d, 5 rats were randomly taken from each group and were killed for examination. The hematoxylin and eosin stain (HE stain) was performed for observation on pathological changes in the rat lung tissues. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis was performed for detection of the mRNA levels of transforming growth factor (TGF-β1) and Plasminogen activator inhibitor-1 (PAI-1). Western blot analysis was applied for detection of the expression of PAI-1. Besides, APC in the bronchoalveolar lavage fluid (BALF) was determined by ELISA. Results ① The HE stain demonstrated that compared with A group, the degree of thickening of alveolar septal the mRNA expressions of TGF-β1 and PAI-1, and the protein expressions of PAI-1 in B group were increased (P<0.05), and the expression of APC in the BALF was decreased (P<0.05). And with prolonged hypoxia, the more significant of these changes were observed. Positive correlation was found between the mRNA levels of PAI-1 and TGF-β1 (r=0.936, P<0.05). ② Compared with B group, the increased thicknesses of alveolar septal in C and D groups were lightened, the mRNA expressions of TGF-β1 and PAI-1, and the protein expression of PAI-1 were decreased (P<0.05), and the expressions of APC in the BALF was increased (P<0.05).With increasing dose, the expression levels of each factor gradually reduced or increased. Conclusion Hypoxia may cause coagulant function abnormality to increase clotting activity and reduce fibrinolytic activity and the anticoagulant activity, inducing alveolar septal thickening, and the mechanism of above changes may related to the TGF-β1 signaling pathways. Breviscapine could improve hypoxia-induced hypercoagulable state that alleviate alveolar septal thickening.