A LOW-THRESHOLD SUSTAINED INWARD CURRENT ACTIVATED AT THE DIASTOLIC POTENTIAL RANGE IN RABBIT SINOATRIAL NODE CELLS

被引:0
|
作者
GUO, JQ [1 ]
ONO, K [1 ]
NOMA, A [1 ]
机构
[1] NANJING COLL TRAD CHINESE MED,DEPT PHYSIOL,NANJING 210029,PEOPLES R CHINA
关键词
PACEMAKER CURRENT; SINOATRIAL NODE; DIASTOLIC DEPOLARIZATION; CA2+ CHANNEL;
D O I
暂无
中图分类号
R5 [内科学];
学科分类号
1002 ; 100201 ;
摘要
The whole-cell voltage clamp was performed in myocytes dissociated from the rabbit sinoatrial node using the collagenase method. After blocking both the hyperpolarization-activated current and the membrane K+ conductance, depolarizations from -80 mV to values in the range -70 to -50 mV induced a sustained current. This low-threshold sustained inward current was blocked by both organic and inorganic Ca2+ channel blockers, but tetrodotoxin 30 mu M was ineffective. Isoprenaline increased this current. It is suggested that this current plays an important role in driving the diastolic depolarization.
引用
收藏
页码:200 / 202
页数:3
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