1、肝缺血再灌注損傷后電解質變化對心肌細胞超微結構的影響 作者：蔣俊丹， 鄭曉春， 陳彥青， 吳曉丹， 黃風怡【關鍵詞】 肝疾病；,腸；,缺血再灌注損傷；,肌細胞,心臟；,電解質；,顯微鏡檢查,電子摘要: 目的觀察大鼠肝門阻斷后缺血再灌注（IR）損傷對心肌細胞超微結構的影響。方法 大鼠氣管切開機械通氣，監測肺動脈壓（PAP）。72只大鼠隨機分為對照組（A組）、肝血流阻斷組（B組）及門靜脈轉流下肝血流阻斷組(C組)。于IR前和IR后1，6 h取左心室前壁心肌組織數塊。血氣分析肝門阻斷期間門脈血pH和電解質；光、電鏡下觀察心肌細胞形態學改變。結果 與A組比較，B，C組IR后PAP顯著升高（P0.05）

2、，但C組較B組更快恢復至阻斷前水平。肝門阻斷期間，B組pH降低顯著（P0.05，）；K+較IR前升幅超過1倍（P0.01），IR后下降，但6 h時仍處于較高水平（P0.05）；Ca2+呈進行性下降。C組變化與A組比較差別無統計意義（P0.05）。電鏡觀察，A組心肌細胞超微結構正常；B組心肌細胞6 h可見線粒體水腫，心肌肌絲斷裂，細胞間隙增大，部分心肌細胞可見壞死區域，結構崩解；C組IR后部分心肌肌絲模糊，線粒體腫脹，心肌細胞局灶性壞死。結論 肝門阻斷后門脈內酸性物質和高鉀血癥直接抑制心肌收縮力，減少心排，腸道IR損傷是引起心肌細胞超微結構損害的主要因素。關鍵詞: 肝疾病； 腸； 缺血再灌注損傷

3、； 肌細胞，心臟； 電解質； 顯微鏡檢查，電子ABSTRACT: ObjectiveTo investigate the myocardial morphologic changes after hepatic portal occlusion(HPO) ischemareperfusion injury. Methods Rats were mechanical ventilated. The animals were randomly divided into 3 groups：(1)control group was shamoperated; (2)HPO group, the ani

4、mals were subjected to reperfusion after 60 min hepatic portal occlusion; (3)bypass group, HPO 60 min while bypassed by caudal lobe. The animals in each group were killed before reperfusion and the end of reperfusion 60 or 360 min. The hemodynamics and portal vein blood gas analysis were measured, t

5、he myocardial cell morphology were studied by optics and electron microscopy.Results Hemodynamics data in both B,C groups showed low cardiac output during HPO phase, and pulmonary artery pressure(PAP) was higher than group A after reperfusion（P0.05）, but in group C the PAP return to baseline was fas

6、ter than group B（P0.05）. Compared with groups A and C, the portal vein pH in group B decreased significantly during HPO but immedially return after reperfusion, simultaneously the K+ remarkablely increased and lasted to 6 h; the Ca2+ decreased gradually（P0.05）. The electron microscopy showed the myo

7、cardial morphology in group A was normal, group C appeared myofilament broken ,mitochondrium swelling,and some cell focus necrosis. Group B was serious than group C, such as mitochondrium edema, there were myofilament and muscle rod broken, cell spaces increasing, and local necrosis or disintegratio

8、n.Conclusion The ischemiareperfusion injury afer HPO may affected myocardial cell and inhibit cardiac contractibility. The interruption of bowel blood stream and reperfusion of intestinal metabolites may be the principal cause of myocardium damage.KEY WORDS: liver diseases; intertines; ischemia repe

9、rfusion injury; myocyes,cardiac; electrolytes; microscopy, electron肝移植和肝門阻斷（hepatic portal occlusion，HPO）手術中肝臟缺血再灌注(ischemiareperfusion，IR)損傷是常見的病理生理表現，其中門靜脈阻斷后腸道IR損傷被認為是術后多臟器功能不全（MOSF）的引擎1，導致肝外多臟器功能損傷。筆者觀察HPO后肝和腸道IR損傷對心肌細胞超微結構的影響。1 動物與方法1.1 動物分組 選取體質量200250 g成年SD雄性大鼠福建醫科大學實驗動物中心，合格證號SCXK(閩20040008)

10、，術前禁食12 h。10%水合氯醛3 mL/kg腹腔麻醉，氣管切開機械通氣（TKR200A，江西特力小動物呼吸機）。肝素500 IU/kg靜脈注射。常規消毒，腹部正中切口入腹，離斷肝周韌帶，中斷肝臟側支循環。經右側頸外靜脈將PE50導管置入后連接壓力換能器（Datex多功能監測儀，芬蘭），確認至肺動脈后固定導管并測定肺動脈壓（PAP）。股動脈置管監測平均動脈壓（MAP）和心率（HR）。燈烤保溫，保持肛溫3637 。 所有大鼠隨機分3組：（1）對照組(A組，n=24)，經腹正中切口入腹，切斷全部肝周韌帶；不作肝血流的阻斷。（2）肝血流阻斷組（B組,n=24），Pringle法阻斷肝十二指腸韌帶，

11、使包括尾葉在內的全部肝葉完全缺血，60 min后開放灌注，肝復流后切除尾葉(約占全肝5%)。（3）門靜脈轉流下肝血流阻斷組（C組,n=24），參照文獻分別阻斷肝左中葉及右葉肝蒂，保留尾葉血供作為門脈回流通道；60 min后灌注，肝復流后切除尾葉。每組各有8只大鼠分別于IR前、IR后1，6 h處死，取左心室前壁心肌組織數塊。1.2 方法全程連續監測。以阻斷前數值為基礎值，并于各時間點取值3次求均值。處死前取門脈血1 mL送檢血氣分析（M3562A,德國Philips公司；測試條美國Irma Trutoint公司，批號139903）。冰面上操作,取左室前壁心肌組織數塊，各1 mm1 mm1 mm，

12、3%戊二醛1.5%多聚甲醛前固定，1%鋨酸1.5%亞鐵氰化鉀后固定，酒精丙酮脫水，環氧樹脂618包埋劑包埋；超薄切片80 nm，醋酸鈾、枸櫞酸鉛染色，透射電鏡(日立Hu12A型、飛利浦208型)觀察、細胞表面和內部超微結構改變并攝像（福建醫科大學電鏡室）。取左室前壁心肌組織數塊，置于中性福爾馬林液中固定過夜，常規取材、脫水、石蠟包埋、HE染色、常規切片觀察。1.3統計學處理 采用SPSS 11.0統計軟件分析，計量資料以xs表示。組間比較采用單因素方差分析，組內比較為配對t檢驗；P0.05為差別有統計學意義。 1鄭曉春,陳彥青,黃風怡,等. 抗壞血酸對腸缺血再灌注損傷后大鼠肺的保護作用J. 中

13、華麻醉學雜志, 2005,25（8）:606607.Hiroshi I,Noribiko K,Yasubiko S,et al. Pringle maneuver and selective inflow occlusion in living donor liver hepatecomyJ. Liver Transplantat, 2004,10(1):771778.董家鴻,何效東,李 昆,等. 大鼠門靜脈轉流下耐受入肝血流阻斷的安全時限J. 消化外科雜志, 2002,1（1）:2024.Liu L,Hakansson C H,Jeppsson B,et al. Extrahepatic m

14、ultiple organ damage following prolonged hepatic inflow interruption: A new experimental findingJ. Med Sci Res, 1994,22:361364.Francisco C,Casar F L,Lidia L P,et al. Long term prodution of reactive oxygen species during perinatal asphyxia in the rat central nervous system: effects of hypothermiaJ. Int J Neurosci, 2003,5:641654.Farmer D G,Anselmo D G,Ghobrial R M