Age‐dependent changes in myosin composition correlate with enhanced economy of contraction in guinea‐pig hearts
Age‐dependent changes in myosin composition correlate with enhanced economy of contraction in guinea‐pig hearts
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肌球蛋白组成的年龄依赖性变化与豚鼠心脏收缩经济性的增强相关
DOI：
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
G. Stienen
中科院分区：
文献类型：
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作者：
J. Velden;A. Moorman;G. Stienen
1用两种针对α-MHC和β-MHC的单抗对幼龄(1~8周龄)和成熟(9~26周龄)豚鼠肌球蛋白重链(MHC)的组成进行了研究。此外，还测量了来自相同心脏的化学剥离的小梁在等长收缩过程中的最大力和ATP消耗率。2 MHC组成随年龄变化。α-MHC分数从年轻时的0.17±0.0 2(n=2 4)下降到成熟时的0.0 4±0.0 1(n=43)。这一变化与张力成本(即每小梁体积/每横截面积的ATP消耗)从年轻时的4.1±0.2mmolkN−1m−1 S−1(n=2 3)下降到成熟心脏的2.5±0.1mmolkN−1 m−1 S−1(n=57)有关。3结果表明，在成熟豚鼠心脏中占主导地位的慢β-MHC亚型比快速α-MHC亚型经济约5倍。力钙敏感性和三磷酸腺苷消耗量随年龄增长而下降，但在出生后几周内趋于稳定。心脏超负荷的长期研究应考虑心脏能量学对MHC组成的明显依赖性。
1 The composition of myosin heavy chains (MHCs) was investigated in young (1‐ to 8‐week‐old) and mature (9‐ to 26‐week‐old) guinea‐pigs using two monoclonal antibodies directed specifically against α‐MHC and β‐MHC. In addition, maximum force and the rate of ATP consumption during isometric contraction were measured in chemically skinned trabeculae taken from the same hearts. 2 An age‐dependent shift in the MHC composition was found. The α‐MHC fraction decreased from 0.17 ± 0.02 (mean ± s.e.m.; n= 24) in young to 0.04 ± 0.01 (n= 43) in mature hearts. This shift was correlated with a decrease in tension cost (i.e. ATP consumption per second per trabecula volume/force per cross‐sectional area) from 4.1 ± 0.2 mmol kN−1 m−1 s−1 (n= 23) in young to 2.5 ± 0.1 mmol kN−1 m−1 s−1 (n= 57) in mature hearts. 3 From the results it follows that the slow β‐MHC isoform, which predominates in hearts of mature guinea‐pigs, is about 5 times more economical than the fast α‐MHC isoform. Calcium sensitivity of force and ATP consumption decreased with age, but stabilized within a few weeks after birth. The pronounced dependence of cardiac energetics on MHC composition should be taken into account in long‐term studies of cardiac overload.
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发育中的禽类心脏的力和钙敏感性的变化。
影响因子：
2.1
作者：
Godt,RE;Fogaça,RT;Nosek,TM
通讯作者：
Nosek,TM
大鼠心肌发育中的张力产生和细丝蛋白亚型。
DOI：
10.1152/ajpheart.1994.267.4.h1589
发表时间：
1994
期刊：
The American journal of physiology
影响因子：
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作者：
Reiser,PJ;Westfall,MV;Schiaffino,S;Solaro,RJ
通讯作者：
Solaro,RJ
影响因子：
20.1
作者：
ANDERSON, PAW;MALOUF, NN;ALLEN, PD
通讯作者：
ALLEN, PD
影响因子：
5
作者：
J. Solaro;Jennifer Van Eyk
通讯作者：
J. Solaro;Jennifer Van Eyk
正常和慢性高血压狒狒的心脏β肌球蛋白重链多样性。
DOI：
10.1172/jci114042
发表时间：
1989
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
Henkel,RD;VandeBerg,JL;Shade,RE;Leger,JJ;Walsh,RA
通讯作者：
Walsh,RA