我们的网站为什么显示成这样?

可能因为您的浏览器不支持样式,您可以更新您的浏览器到最新版本,以获取对此功能的支持,访问下面的网站,获取关于浏览器的信息:

|本期目录/Table of Contents|

乙酰胆碱对离体豚鼠心房肌动作电位及其脱敏的影响(PDF)

《心脏杂志》[ISSN:1009-7236/CN:61-1268/R]

期数:
2001年第3期
页码:
165-169
栏目:
论著
出版日期:
2001-05-01

文章信息/Info

Title:
The effect of acetylcholine on desensitization of action potential in guinea-pigs atrial muscles
作者:
张凤杰1臧伟进1于晓江1马志一1臧益民2
1西安交通大学医学院心血管生理药理研究室,陕西 西安 710061;2 第四军医大学生理学教研室;
Author(s):
Zhang Feng-jie 1Zang Wei-jin 11Yu Xiao-jiang1Ma Zhi-yi1 Zang Yi-ming2
1 Division at Cardiovascular Physiology & Pharmacology, Xi'an Jiaotong University, Xi'an Shaanxi 710061, China; 2 Department of Physiology, Fourth Military Medical University,Xi'an Shaanxi 710032, China
关键词:
乙酰胆碱 心肌 心房 动作电位 脱敏
Keywords:
acetylcholinemyocardiumHeart atriumaction potential durationdesensitization
分类号:
R331.38
DOI:
-
文献标识码:
A
摘要:
目的 研究迷走神经递质乙酰胆碱(ACh)对离体豚鼠心房肌细胞动作电位(AP)的影响及其对心房肌的脱敏,探讨脱敏可能发生的机制.方法 采用标准玻璃微电极细胞内记录方法,观察不同浓度(0.01,0.1,1 μmol/L) ACh对心房肌细胞AP的影响及对动作电位时程( APD)和收缩力的脱敏现象,并观察了受体或通道水平的阻断剂阿托品、氯化铯 (CsCl)对ACh所致的心房肌APD脱敏的影响.结果 ①0.01,0.1,1 μm ol/L ACh分别缩短APD的变化率为(6.02±1.04)%,(14.20±3.79)%,(30.20±3.65)%.②0. 01μm ol/L ACh对心房肌细胞没有脱敏;0.1 μmol/L ACh对心房肌细胞APD有轻微脱敏,脱敏持续时间为1 min;而1 μmol/L ACh对心房肌细胞APD脱敏明显,脱敏持续时间为5 min.③1 μ mol /L阿托品与20 mmol/L CsCl并不能阻断1 μmol/L ACh对心房肌细胞APD的脱敏.结论 ACh缩短 APD的作用随浓度增大而增大;ACh对离体豚鼠心房肌细胞APD的脱敏有浓度依赖性与时间依赖性;脱敏的发生可能与毒蕈碱型胆碱能受体及Ik,ACh电流有关.
Abstract:
AIM To investigate the mechanism underlying the effects of ACh on desensitization of action potential in guinea pigs atrial muscles. METHODS Using standard microelectrodes and force transducer we recorded the effects and desensitization of ACh (0.01,0.1,1μmol/L) and blockers (such as atropine, CsCl) on the action potential duration(APD) and force contraction in atrial muscles. RESULTS ①0.01,0.1,1μmol/L ACh shortened the APD by (6.02±1.04)%,(14.20±3.79)% and (30.20±3.65)% respectively. ②0.01μmol/L ACh has no desensitization and the time of desensitization at 0.1 and 1μmol/L ACh lasted 1min and 5min, respect ively. ③The desensitization at 1μmol/L Ach could not be blocked by 1μmol/L atropine, 20 mmol/L CsCl. But atropine or CsCl could decrease the effect of shortening APD caused by ACh. CONCLUSION The effect of desensitization on APD to ACh in atrial cells is concentration and time-dependent, these effects maybe related to the change of the muscarinic receptor and the potassium channel.

参考文献/References

[1] 臧伟进, 臧益民. 乙酰胆碱对心脏的作用及离子机制[J]. 心功能杂志, 1993, 5 (3) : 194- 197.

[2] 臧伟进, 臧益民. 心脏对乙酰胆碱的脱敏现象[J]. 心功能杂志,1993, 5 (4) : 284.

[3] Shui Z, Boyett MR, Zang WJ , et al. Receptor kinase-dependent desensi tization of the muscarinic K+ current in rat atrial cells[J]. J P hysiol, 1995, 487 (2) : 359- 366.

[4] Zang WJ , Yu XJ , Honjo H, et al. On the role of G protein activation and phos phorylation in desensitization to acetylcholine in guinea-pig atrial cells. [J]. J Physiol, 1993, 464: 649- 679.

[5] Yang ZK, Boyett MR, Janvier SO, et al. Regional differences in the neg ative inotropic effect of acetylcholine within the Canine Ventricle[J]. J P hysiol, 1996, 492 (3) : 789- 806.

[6] 徐江平, 童国明, 刘传馈. 毒蕈碱样乙酰胆碱受体的分子药理学研究进展[A]. 金正均, 王永铭, 苏定冯. 药理学进展[M ]. 第3版. 上海: 科学出版社, 1999. 232- 241.

[7] Shui Z, Boyett MR, Zang WJ. ATP-dependent desensitization of the musca rinic K+ channel in rat atrial cells[J]. J Physiol, 1997, 505 (1) : 77- 93.

[9] Kurachi Y. G protein regulation of cardiac muscarinic potassium channel[J ] . Am J Physiol, 1995, 269: C821- C830.

[8] Hong SG, Pleumsamran A , Kim D. Regulation of atrial muscarinic K+ ch anne l activity by a cytosolic protein via-protein-independent pathway [J ]. Am J Physiol, 1996, 270: H526- H537.

[10] BünemannM , Lee KB, Rylaarsdam RP et al. Desensitization of G-Pr otein-coupled receptors in the cardiovascular system [J ].Annu Rev Physiol, 1999, 61: 169- 192.

备注/Memo

备注/Memo:
收稿日期:2000-09-12.基金项目:国家自然科学基金资助课题!( No.39870334 ;39970273 )
更新日期/Last Update: 2001-05-01