Tetramethylpyrazine对血管平滑肌A7r5细胞内钙离子浓度

Tetramethylpyrazine对血管平滑肌A7r5细胞内钙离子浓度的影响
黄家乐1,2,3 许汝宁4 吴可夫5 苏翔6 陈保罗7 郑瑞棠8
1.台湾台中中国医药大学暨附设医院麻醉部
2.台湾台中中国医学大学医学研究所
3.台湾台中中国医学大学动物实验研究中心
4.台湾台北长庚纪念医院麻醉部
5.台湾屏东基督教医院麻醉科
6台湾台南奇美医院麻醉科暨台南成功大学基础医学研究所
7.台北医学大学万芳医院心脏内科及临床研究中心
8.台湾台南成功大学医学院药理研究所
目的: Tetramethylpyrazine(TMP)对于血管组织和平滑肌细胞都具有像钙
离子阻断剂的作用.而TMP对血管上细胞内钙离子浓度的影响强度仍然不明
确.本篇研究以培养的血管平滑肌A7r5细胞,并利用对钙离子敏感的染剂
Fura-2作为指示剂,探讨TMP对细胞内钙离子浓度的影响.
方法:我们先前的研究已显示TMP使血管扩张的作用主要是透过对钙离
子流入的抑制.本篇研究则是利用对钙离子敏感的染剂Fura-2来测量A7r5细
胞中的游离钙离子浓度.细胞内游离钙离子的量是用Hitachi F-2000分光光度
计的520 nm的发散波长及340nm和380nm的激发态波长去测量.游离的钙离
子浓度对vasopressin(sigma Chemical, St Louis, MNO, USA)及phenylephrine
(Sigma Chemical)反应的改变则是用正常含钙的PSS来评估.实验程序在投予
vasopressin和phenylephrine前310分钟先给予TMP,以测试TMP所产生的钙
离子拮抗作用.使用ANOVA作为统计分析,p值少于0.05视为有意义.
结果:在A7r5细胞中,由vasopressin(1μmol/L)及phenylephrine(1μ
mol/L)所产生的钙离子浓度的增加可被TMP(0.01μmol/L至1000μmol/L)所
降低,钙离子浓度由1271.3±69.2降至 592.2±48.6 nmol/L(vasopressin组) 及
820.9±83.1 降至378.4±58.8 nmol/L(phenylephrine组),其降低程度与TMP所 （科教范文网http://fw.NSEAC.com编辑发布）
使用的浓度成比(呈concentration- dependent manner).
结论:本实验结果显示,TMP降血压的机转乃透过抑制钙离子流入细胞内
而达到其血管扩张的作用
中华麻醉在线 http://www.csaol.cn 2007年9月
Title: The Influence of Tetramethylpyrazine on The Calcium Influx in Cultured
Aortic Smooth Muscle Cells
Authors: Kar-Lok Wong1,2,3, Yue-Ling Hui4, Ko Fu Wu5, Edmund So6,7*,
Paul Chan8 , Juei-Tang Cheng9 (*Correspondence author)
Institute: 1. Dept of Anesthesiology, China Medical University & Hospital, Taiwan
2. Institute of Medical Sciences, China Medical University, Taichung, Taiwan
3. Animal Lab & Research Center, China Medical University, Taichung, Taiwan
4. Dept of Anesthesiology, Chang Gung Memorial Hospital, Taipei, Taiwan
5. Dept of Anesthesia, Ping-Tung Christian Hospital, Ping-Tung, Taiwan
6. Department of Anesthesiology, Chi-Mei Foundation Hospital, Tainan, Taiwan
7. Institute of Basic Medical Sciences, National Cheng-Kung University, Taiwan
8. Department of Cardiology, Taipei Medical University Hospital, Taipei, Taiwan
9. Institute of Pharmacology, National Cheng-Kung University, Tainan, Taiwan
Aim of investigation: Tetramethylpyrazine (TMP) has a calcium
antagonist-like action in vascular tissue and smooth muscle cells. The magnitude by
which TMP affects intracellular calcium ion concentrations ([Ca2+']i) in vascular
vessels has remained unclear. The present study is to investigate the effect of
TMP on intracellular calcium concentrations ([Ca2+']i) in cultured vascular smooth
muscle (A7r5) cells using the Ca2+-sensitive dye Fura-2 as an indicator.
Methods: Our previous studies have shown that the vasodilatation effect
of TMP was mediated mainly through calcium influx inhibition. In the present study,
the measurement of intracellular free calcium concentrations ([Ca2+]i) in A7r5 cells
was performed using the calcium-sensitive dye Fura-2 method. The [Ca2+]i was
measured by using of an emission wavelength of 520 nm and alternating excitatory （转载自http://www.ＮＳＥＡＣ.com中国科教评价网）
wavelengths of 340 and 380 nm in the Hitachi F-2000 spectrophotometer. The
change in [Ca2+]i in response to vasopressin (Sigma Chemical, St Louis, MO,
USA) and phenyephrine (Sigma Chemical) was evaluated using normal PSS
containing calcium. TMP administered 30 min before vasopressin and
phenylephrine was used to observe Ca2+ antagonism by TMP. ANOVA was used for
statistical analysis, p<0.05 were considered significant.
Results: The increase of [Ca2+]i in A7r5 cells produced by vasopressin (1
μmol/L) or phenylephrine (1 μmol/L) was attenuated by TMP (0.01 μmol/L to 1000
μmol/L) from1271.3±69.2 to 592.2±48.6 nmol/L and 820.9±83.1 to 378.4±58.8
nmol/L respectively in a concentration-dependent manner.
Conclusions: These results indicate that the mechanism of vasodilative effect
of TMP was via an inhibition of calcium influx into smooth muscle cells of blood
vessel.