Intracellular potassium and sodium activities of chick ventricular muscle during embryonic development.
Intracellular potassium and sodium activities of chick ventricular muscle during embryonic development.
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胚胎发育过程中鸡心室肌的细胞内钾和钠活性。
DOI：
10.1113/jphysiol.1980.sp013416
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
Sheu,SS
中科院分区：
文献类型：
--
作者：
Fozzard,HA;Sheu,SS
1.利用离子选择性微电极研究了鸡胚心肌静息电位的基础。膜静息电位从-65超极化。4+/-1。1 mV(平均值+/-S.E.)从出生4天到-75岁。8+/-0。18日龄6 mV。动作电位超调从+19增加。8+/-0。9日龄4天至+33天。1+/-0。18日龄6 mV。2.用离子选择微电极测得的细胞内K+活性由71升高。3+/-1。日龄4天至89天时为9 mm。9+/-1。1日龄18天。细胞内Na+活性从12下降。5+/-0。4%至7%。0+/-0。3毫米，在同一时期。膜静息电位与计算的钾平衡电位之差随生长发育而减小。从恒定场方程估计的PNA/PK从0下降。012，4日龄至0。005，出生18天。3.在发育过程中，静息电位的超极化和动作电位超调的增加可以用细胞内K+活性的升高和细胞内Na+活性的下降来解释，就像Na-K交换泵变得更加活跃一样。
1. The basis of the resting potential of chick embryo ventricular muscle was studied by use of ion‐selective micro‐electrodes. Membrane resting potential hyperpolarized from ‐65 . 4 +/‐ 1 . 1 mV (mean +/‐ S.E.) at age 4 day to ‐75 . 8 +/‐ 0 . 6 mV at age 18 day. Action potential overshoot increased from +19 . 8 +/‐ 0 . 9 at age 4 day to +33 . 1 +/‐ 0 . 6 mV at age 18 day. 2. Intracellular K+ activity measured with ion‐selective micro‐electrodes increased from 71 . 3 +/‐ 1 . 9 mM at age 4 day to 89 . 9 +/‐ 1 . 1 at age 18 day. Intracellular Na+ activity decreased from 12 . 5 +/‐ 0 . 4 to 7 . 0 +/‐ 0 . 3 mM during the same period. The difference between membrane resting potential and the calculated potassium equilibrium potential decreased with development. PNa/PK estimated from the constant field equation decreased from 0 . 012 at age 4 day to 0 . 005 at age 18 day. 3. The hyperpolarization of resting potential and the increased action potential overshoot during development could be explained by a rise in intracellular K+ activity and a fall in intracellular Na+ activity, as if the Na‐‐K exchange pump became more active.