牵张刺激对乳大鼠心房肌细胞瞬时外向钾电流和动作电位的影响

胥亚楠; 杨龙; 邓春玉; 杨天和; 罗淋; 覃智芳; 唐倩; 杨君

doi:10.13201/j.issn.1001-1439.2014.07.022

牵张刺激对乳大鼠心房肌细胞瞬时外向钾电流和动作电位的影响

- 1 贵州省人民医院心内科, 贵阳医学院附属人民医院(贵阳, 550002);
- 2 遵义医学院第三附属医院;
- 3 广东省人民医院
基金项目:
国家自然科学基金项目 (No:81060018)

详细信息

通讯作者: 杨龙,E-mail:yanglong1001@163.com

中图分类号: R541.4

收稿日期: 2013-10-11

Effects of stretch on transient outward potassium and action potential of cultured atrial neonatal myocytes

- 1 Department of Cardiology, Guizhou Provincial People's Hospital, Affiliated to Guiyang Medical College, Guiyang, 550002, China;
- 2 the Third Affiliated Hospital, Zunyi Medical College;
- 3 People's Hospital in Guangdong Provence

More Information

Corresponding author: YANG Long, E-mail: yanglong1001@163.com

Received Date: 11 October 2013

摘要

摘要: 目的:探究牵张刺激对乳大鼠心房肌细胞瞬时外向钾电流 (Ito) 和动作电位时程 (APD) 的影响。方法:1d龄SD乳鼠, 采用胰酶消化法分离获得心房肌细胞。于细胞牵引装置培养24h分组:对照组:不予牵张刺激;牵张组:牵张增加12%硅胶膜面积24h。采用膜片钳全细胞记录方法记录两组细胞膜Ito和APD的变化。结果:在+20~+60mV刺激电压水平, 牵张组Ito电流密度与对照组相比明显降低[(1.6±0.4) pA/pF:(12.1±2.9) pA/pF, P＜0.01, n=9];牵张组动作电位复极50% (APD50)、复极90% (APD90) 均明显缩短[(10.5±1.4) ms:(15.5±2.4) ms, (30.0±2.8) ms:(56.3±3.6) ms;均P＜0.01, n=9]。结论:牵张刺激可降低乳鼠心房肌细胞Ito电流密度, 缩短APD, 这可能是压力负荷增大致心房电重构的基础之一。
- 牵张 /
- 心房肌细胞 /
- 全细胞膜片钳技术 /
- 瞬时外向钾电流 /
- 动作电位
Abstract: Objective: To investigate stretch on transient outward potassium current (Ito) and action potential (AP) of cultured atrial neonatal myocytes.Method: Neonatal rat atrial cardiomyocytes were isolated and cultured on silicone sheeting for 24 hours.One group with silicone membrane area increased by 12% was cultured for 24 hours, samples without stretched were regarded as controls.Ito and AP were recorded by whole-cell patch clamp technique.Result: With the+20-+60clamp potential, compared with control group, the density of Ito was significantly reduced in stretched myocytes[(1.6±0.4) pA/pF vs (12.1±2.9) pA/pF, P＜0.01, n=9].The AP duration (APD) at 50% and 90% level of repolarization (APD50and APD90) of stretched group were visibly shorter than control group[(10.5±1.4) ms vs (15.5±2.4) ms, (30.0±2.8) ms vs ((56.3±3.6) ms, P＜0.01, respectively].Conclusion: The stretch can reduce density of Ito and shorten the APD of atrial myocytes of rat, which is attributed to atrial electrical remodeling induced by pressure overload.
- mechanical stretch /
- atrial myocytes /
- whole-cell patch clamp technique /
- transient outward potassium current /
- action potential

HTML全文

参考文献(17)

[1]	HEERINGA J, VAN DER KUIP D A, HOFMAN A, et al.Prevalence, incidence and lifetime risk of atrial fibrillation:the Rotterdam Study[J].Eur Heart J, 2006, 27:949-953.
[2]	BENJAMIN E J, LEVY D, VAZIRI S M, et al.Independent risk factors for atrial fibrillation in apopulation-based cohort.The FraminghamHeart Study[J].JAMA, 1994, 271:840-844.
[3]	MEDI C, KALMAN J M, SPENCE S J, et al.Atrial electrical and structural changes associated with longstanding hypertension in humans:implications for the substrate for atrial fibrillation[J].JCE, 2011, 22:1317-1324.
[4]	KIM S J, CHOISY S C, BARMAN P, et al.Atrial remodeling and the substrate for atrial fibrillation in rat hearts with elevated afterload[J].Circ Arrhythm Electrophysiol, 2011, 4:761-769.
[5]	CORRADI D, CALLEGARI S, MAESTRI R, et al.Differential structural remodeling of the leftatrial posterior wall in patients affected by mitral regurgitation with or without persistent atrial fibrillation:a morphological and molecular study[J].JCE, 2012, 23:271-279.
[6]	罗淋, 刘志琴, 杨龙, 等.大鼠乳鼠原代心房肌细胞培养的方法及鉴定[J].国际心血管病杂志, 2013, 40 (3):112-115.
[7]	杨龙, 何炯红, 袁正强, 等.替米沙坦抑制钙调神经磷酸酶调控牵张刺激诱导乳鼠心房肌细胞Cav1.2mRNA的表达[J].贵州医药, 2011, 35 (9):771-775.
[8]	SAYGILI E, RANA O R, SAYGILI E, et al.Losartan prevents stretch-induced electrical remodeling in cultured atrial neonatal myocytes[J].Am J Physiol Heart Circ Physiol, 2007, 292:H2898-2905.
[9]	RANA O R, ZOBEL C, SAYGILI E, et al.A simple device to apply equibiaxial strain to cells cultured on flexible membranes[J].Am J Physiol Heart Circ Physiol, 2008, 294:H532-540.
[10]	SAYGILI E, RANA O R, MEYER C, et al.Theangiotensin-calcineurin-NFAT pathway mediates stretch-induced up-regulation of matrix metalloproteinases-2/-9in atrial myocytes[J].Basic Res Cardiol, 2009, 104:435-448.
[11]	DE JONG A M, MAASS A H, OBERDORF-MAASS S U, et al.Cyclical stretch induces structural changes in atrial myocytes[J].J Cell Mol Med, 2013, 17:743-753.
[12]	YAMASHITA T, MURAKAWA Y, HAYAMI N, et al.Short-term effects of rapid pacing on mRNA level of voltage-dependent K channels in rat atrium:electrical remodeling in paroxysmal atrial tachycardia[J].Circulation, 2000, 101:2007-2014.
[13]	王德胜, 黄从新, 郑文, 等.心房颤动心房肌细胞短暂外向钾电流的特点[J].中国心脏起搏与心电生理杂志, 2001, 15 (2):89-91.
[14]	WIJFFELS M C, KIRCHHOF C J, DORLAND R, et al.Atrial fibrillation begets atrial fibrillation.A study in awake chronically instrumented goats[J].Circulation, 1995, 92:1954-1968.
[15]	DOBREV D, RAVENS U.Remodeling of cardiomyocyte ion channels in human atrial fibrillation[J].Basic Res Cardiol, 2003, 98:137-148.
[16]	VAN WAGONER D R.Electrophysiological remodeling in human atrial fibrillation[J].Pacing Clin Electrophysiol, 2003, 26:1572-1575.
[17]	周婕, 谭树华, 张善春.心肌瞬时外向钾电流与相关疾病的研究进展[J].中国心脏起搏与心电生理杂志, 2012, 26 (3):265-267.