1、VEGF在大鼠缺血再灌注損傷肝組織中的表達及其意義         08-07-05 15:52:00     作者：ZHU Qiu-we    編輯：studa0714【摘要】  目的： 探討血管內皮生長因子（vascular endothelial growth factor，VEGF）在缺血再灌注損傷肝組織中的表達及意義。方法： 利用雄性SD大鼠建立部分肝血流阻斷動物模型，肝血流阻斷90 min后恢復血流灌注，再灌注后1

2、,6 h處死大鼠收集標本。分別采用全自動生化分析儀、HE 染色，比色法、ELISA法測定血清轉氨酶(ALT,AST)，肝組織病理改變,肝組織髓過氧化物酶（MPO）的活性以及VEGF蛋白的含量。結果： 與假手術組相比，缺血再灌注組（I/R組）缺血肝臟MPO活性，肝組織內VEGF蛋白的含量以及ALT，AST在再灌注1 h即升高，且缺血再灌注6 h時較1 h明顯升高；缺血肝臟病理切片可見大量炎癥細胞浸潤，6 h炎癥反應更為劇烈，部分肝細胞呈點狀壞死。結論： VEGF蛋白表達的上調可能參與了大鼠肝臟缺血再灌注過程中肝臟的損傷。 【關鍵詞】  肝臟； 缺血； 再灌注損傷； 血管內皮生長因子Ab

3、stract  Objective: To investigate the expression of vascular endothelial growth factor(VEGF) in the liver ischemia/reperfusion injury and significance.Methods： The male SD rats were used to establish partial hepatic vascular exclusion animal model. After ischemia for 90 min，SD rats liver were r

4、eperfused，and then liver specimens were collected at 1 h and 6 h after reperfusion respectively. Routine assays were performed for testing the levels of alanine aminotransferase(ALT),aspartate aminotransferase（AST）and the activity of hepatic myeloperoxidase(MPO).The changes of VEGF protein in ischem

5、ic liver lobes were determined by ELISA. The liver tissues pathological changes were evaluated in hematoxylin and eosin(HE) stained. Results： After 90 min of partial liver ischemia,the AST,ALT level in I/R group was significantly increased as compared with the sham-operated(SH) group, and AST,ALT le

6、vel at the 6 h reperfusion was markly higher than that at the 1 h reperfusion.The expression of VEGF protein and the MPO activity in hepatic tissues were remarkably up-regulated in I/R group than in the SH group at the time point of 1 h and 6 h reperfusion.They were higher at 6 h reperfusion than th

7、at at 1 h. For HE staining, the infiltration of many inflammatory cells was observed in liver tissue and became much severer at 6 h posT-reperfusion liver tissue.  Conclusion： The up-regulation of VEGF protein in hepatic I/R injury process might be involved in the process of liver injury.Key wo

8、rds  liver； ischemia； reperfusion injury； vascular endothelial growth factor缺血再灌注損傷是肝移植、復雜肝切除術中常常涉及的共同病理過程，多種細胞因子參與并介導了肝缺血再灌注損傷過程中的各個環節。近年來,國外許多學者研究發現血管內皮生長因子（vascular endothelial growth factor，VEGF）與缺血再灌注損傷密切相關1,2。血管內皮生長因子又稱血管通透因子(vascular permeability factor，VPF)，它是一種二聚糖，蛋白相對分子質量為3445 kD,由兩個相

9、同的亞基組成，是內皮細胞產生的特異性促有絲分裂原,具有促進內皮細胞增生、遷移，增加血管通透性和加速新血管形成的作用。本文通過觀察大鼠肝缺血再灌注模型中肝組織內VEGF蛋白的表達，探討其在肝缺血再灌注損傷中的作用。 1  材料與方法1.1  主要試劑   大鼠血管內皮生長因子ELISA試劑盒購自武漢博士德生物工程有限公司；髓過氧化物酶（MPO）測試盒購自南京建成生物工程研究所。  1.2  動物分組及模型建立   健康雄性SD大鼠，體質量（300±20）g，江蘇大學醫學院實驗動物中心提供。將SD大鼠隨機分成假手術組、

10、肝缺血再灌注1,6 h模型組，每組6只。手術前12 h動物開始禁食而自由飲水，腹腔內注射戊巴比妥鈉（30 mg/kg）麻醉后，常規消毒、鋪巾，上腹正中切口逐層進腹，分離肝門，無損傷動脈夾阻斷肝臟中葉、左葉血供，90 min后恢復缺血肝葉血供，建立70肝臟缺血再灌注損傷模型，假手術組僅行麻醉、開腹、不阻斷血流。各組在相應時間點處死大鼠，留取門靜脈血清和缺血區肝臟組織。  1.3  肝臟VEGF,MPO及肝功能檢測  肝臟VEGF蛋白含量采用大鼠血管內皮生長因子ELISA試劑盒進行檢測，肝組織中的MPO采用髓過氧化物酶測試盒進行檢測，操作按試劑盒說明進行。血清丙氨酸氨基轉換酶(ALT),天冬氨酸氨基轉換酶(AST)水平應用Olympus Au2700全自動生化分析儀(日本)進行分析,判定肝臟功能改變情況。  1.4  肝臟組織學檢查