The spontaneous action potential of rabbit atrioventricular node cells.
The spontaneous action potential of rabbit atrioventricular node cells.
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兔房室结细胞自发动作电位。
DOI：
10.2170/jjphysiol.30.529
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
H. Irisawa
中科院分区：
文献类型：
--
作者：
S. Kokubun;M. Nishimura;A. Noma;H. Irisawa
兔房室结(A-V)大小约为5×3 mm，分成15个小标本(0.5×0.5 mm)。大多数标本继续放出自发动作电位，不同标本的动作电位形态几乎相同。动作电位的幅度(98 MV)和最大上升速率(11V/s)与完整的房室结(幅度98 mV，最大上升速率12V/s)相似。在这些小标本中，静息膜电位(-44 mV)比解剖前完整的房室结标本的负值(-62 mV)低约20 mV。这些小的房室结标本的自发放电是由于静息膜电位低所致。在IS阻滞剂的作用下，小标本变得不兴奋，尽管TTX对动作电位没有显著影响。去极化电流脉冲停止后可观察到后超极化现象。结果表明，慢内向电流和慢外向电流动力学对自发房室结动作电位的产生具有重要作用。
The rabbit atrioventricular (A-V) node, with dimensions of approximately 5 X 3 mm was dissected into 15 small specimens (0.5 X 0.5 mm). A majority of the specimens continued to discharge spontaneous action potentials, the action potential configuration being almost identical in different specimens. The amplitude (98 mV) and the maximum rate of rise of the action potential (11 V/sec) were similar to those recorded from the intact A-V node (amplitude 98 mV, maximum rate of rise of action potential 12 V/sec). In these small specimens, the "resting membrane potential (-44 mV)" was approximately 20 mV less negative than that in the intact A-V node preparation (-62 mV) before the dissecting procedure. The spontaneous discharge in these small A-V node specimens was attributed to the low resting membrane potential. The small specimen became inexcitable under the effects of blockers of is, though TTX had no significant effect on the action potential. The after-hyperpolarization was observed after cessation of the depolarizing current pulse. It is concluded that the slow inward current and the slow kinetics of the outward current contribute to the generation of the spontaneous A-V node action potentials as in the sinoatrial node.