一氧化氮对缺氧豚鼠心肌细胞游离钙浓度的影响  

The Influence of Nitrous Oxide on Intracellular Free Calcium Concentration during Hypoxia in Guinea Pigs

作　　者：赵昕[1] 白小涓[2] 曹云鹏[3] 王景全[2] 于雅媛[2] 孙景兰[1] 

机构地区：[1]沈阳医学院附属中心医院循环内科,辽宁省沈阳市110001 [2]中国医科大学附属第一医院循环内科 [3]中国医科大学附属第一医院神经内科

出　　处：《中国循环杂志》2000年第6期370-372,共3页Chinese Circulation Journal

基　　金：国家教委留学归国启动基金资助项目

摘　　要：目的 :探讨左旋精氨酸 (L - arginine,L - arg)及 NG-亚硝基 - L -精氨酸甲酯 (NG- nitric- L - arginine- methyl ester,L NAME)对缺氧豚鼠心肌细胞内游离钙浓度 ([Ca2 + ]i)变化影响。　　方法 :采用离体豚鼠心 L angendorff法灌注 ,胶原酶 I型分离细胞 ,再用荧光指示剂方法 (Fure- 2 / AM)标记心肌[Ca2 + ]i 变化。分为 3组 :对照组、L - arg组和 L - NAME组。观察缺氧后心肌 [Ca2 + ]i的变化。　　结果 :1正常氧状态下 ,心肌 [Ca2 + ]i 均值为 12 0 .0± 14.3nmol/ L(n=10 )。2缺氧状态下心肌 [Ca2 + ]i 增加与缺氧时间 (程度 )成正相关 ,相关系数 r为 0 .99左右。 3一氧化氮 (NO)在缺氧条件下对心肌 [Ca2 + ]i 有影响。　　结论 :在短期轻度缺氧条件下 ,NO不足使心肌 [Ca2 + ]i 增加 ,若能设法增加细胞内的 NO含量 ,可以提高心肌细胞的自我保护作用。在长时间重度缺氧条件下 。Objective:We studied the effects of L arginine (L arg,nitric oxide precursor) and N G nitric L arginine m ethyl ester (L NAME,nitric oxide synthase inhibitor) on intracellular free calcium concentration of myocardial cell ([Ca 2+ ] i) under hypoxic condition. Methods:We adopted guinea pig heart Langendorff instillation.The myocardial cells were isolated by collagenase (Tyoe I,sigma) and marked by fluorescence ratio imaging.The suspension of myocardial cells was assigned to three groups:L arg,L NAME,and the control.Each group was exposed to hypoxia before determination of [Ca 2+ ] i. Results:①In normoxic state,[Ca 2+ ] i was 120 0±14 3 nmol/L ( n =10).②In hypoxic state,the increased [Ca 2+ ] i of myocardial cells was proportional to the time (degree) of hypoxia.Correlation coefficient (r) was about 0 99.③Under the condition of hypoxia Nitrons oxide was more sensitive to myocardial cells than ordinary oxygen pressure. Conclusion:In short term mild hypoxia,the shortage of NO results in the increase of [Ca 2+ ] i.The increased [Ca 2+ ] i may improve self protected perfomance of myocardial cells.In condition of long term severe hypoxia,NO may be toxic for myocardial cells.

关 键 词：左旋精氨酸 NG-亚硝基-L-精氨酸甲酯 心肌细胞内游离钙 心肌缺氧 

分 类 号：R542.2[医药卫生—心血管疾病]