Modulation of Ca2+ transient decay by tension and Ca2+ removal in hyperthyroid myocardium.
Modulation of Ca2+ transient decay by tension and Ca2+ removal in hyperthyroid myocardium.
复制标题
甲状腺机能亢进心肌中张力和 Ca2 去除对 Ca2 瞬时衰减的调节。
DOI：
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发表时间：
1999
影响因子：
--
通讯作者：
S. Kurihara
中科院分区：
文献类型：
--
作者：
T. Ishikawa;Hidetoshi Kajiwara;S. Kurihara
我们研究了肌浆网（SR）和Na+/Ca2+交换器在甲状腺功能正常（Eu）和甲状腺功能亢进（Hy）心肌中Ca2+瞬态（CaT）衰减的张力依赖性变化中的作用。甲状腺素诱导Hy可提高SR Ca2+的摄取率。采用aequorin法，在不同条件下（改变肌肉长度和溶液中Ca2+浓度）同时测量CaT和抽搐收缩张力。在两组中，CaT （DT）衰减时间对发育张力有显著依赖性，但Hy组DT对张力的依赖性明显小于Eu组。在咖啡因（3 mM）的存在下，Hy中DT的张力依赖性与Eu中一样明显。用Li+取代Na+对Na+/Ca2+交换器的抑制不影响Hy的依赖性。Hy中标准化的额外Ca2+，即响应快速长度变化的Ca2+浓度变化，与Eu相似。两组不同长度（1.9微米和2.3微米）皮肤小梁的pca张力关系几乎相同。这些结果表明，肌钙蛋白C对Ca2+亲和力的张力依赖性变化在Eu和Hy心肌中都起作用，DT的张力依赖性变化受到SR Ca2+摄取速率的影响。
We investigated the contribution of sarcoplasmic reticulum (SR) and Na+/Ca2+ exchanger in the tension-dependent change in the decay of the Ca2+ transients (CaT) in euthyroid (Eu) and hyperthyroid (Hy) myocardium. Hy was induced by thyroxine treatment to enhance the rate of SR Ca2+ uptake. With the use of the aequorin method, CaT and tension in twitch contraction were simultaneously measured under various conditions (changing muscle length and Ca2+ concentration in solution). In both groups, the decay time of CaT (DT) showed a significant dependence on the developed tension, but the tension dependence of DT in Hy was significantly less than in Eu. In the presence of caffeine (3 mM), the tension dependence of DT in Hy became apparent as in Eu. Inhibition of Na+/Ca2+ exchanger by replacing Na+ with Li+ did not affect the dependence in Hy. The normalized extra Ca2+, which is the Ca2+ concentration change in response to a quick length change, in Hy was similar to that in Eu. pCa-tension relations of skinned trabeculae measured at different lengths (1.9 and 2.3 micrometer) were nearly identical in both groups. These results indicate that the tension-dependent change in the affinity of troponin C for Ca2+ works in both Eu and Hy myocardium and that the tension-dependent change in DT is influenced by the Ca2+ uptake rate of SR.
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影响因子：
20.1
作者：
KISS, E;JAKAB, G;EDES, I
通讯作者：
EDES, I
影响因子：
20.1
作者：
ARAI, M;OTSU, K;PERIASAMY, M
通讯作者：
PERIASAMY, M
甲状腺状态的变化影响大鼠心室肌细胞的 pHi 和 Nai 稳态。
影响因子：
5
作者：
Wolska,BM;Averyhart-Fullard,V;Omachi,A;Stojanović,MO;Kallen,RG;Solaro,RJ
通讯作者：
Solaro,RJ
影响因子：
5.5
作者：
ALLEN, DG;KURIHARA, S
通讯作者：
KURIHARA, S
哺乳动物心室肌中的钙瞬变。
影响因子：
39.3
作者：
Allen,DG;Kurihara,S
通讯作者：
Kurihara,S