Dexamethasone-induced hypertrophy in rat neonatal cardiac myocytes involves an elevated L-type Ca(2+)current.
Dexamethasone-induced hypertrophy in rat neonatal cardiac myocytes involves an elevated L-type Ca(2+)current.
复制标题
地塞米松诱导的大鼠新生心肌细胞肥大涉及 L 型 Ca(2) 电流升高。
DOI：
10.1006/jmcc.1999.0990
复制
发表时间：
1999
影响因子：
5
通讯作者：
Li,M
中科院分区：
文献类型：
--
作者：
WhitehurstJr,RM;Zhang,M;Bhattacharjee,A;Li,M
地塞米松引起婴儿肥大的机制尚未明确。在本研究中，我们研究了L型钙电流在地塞米松诱导的新生大鼠心肌细胞肥大中的作用。通过细胞质膜电容的测量，我们发现地塞米松处理的细胞大小比对照细胞大。1μ地塞米松处理细胞48h后，L型钙电流密度显著增加，但不影响电流的电压依赖性激活和稳态失活。电流密度的增加与编码L型钙通道亚单位α1C的mR NA转录增加有关。地塞米松处理后，Fura-2荧光检测法测定的细胞内钙瞬变峰值增加。最后，我们已经证明，地塞米松的肥大效应(以每细胞蛋白质含量的比率为特征)可被L型特异性拮抗剂硝苯地平阻断。结论：地塞米松诱导的新生大鼠心肌细胞肥大过程中可能存在L型钙电流的升高。
The mechanism responsible for dexamethasone-induced hypertrophy in infants has not been defined. In this study, we have investigated the role ofl -type Ca2+currents in the development of dexamethasone-induced hypertrophy in rat neonatal cardiac myocytes. Using cytoplasmic membrane capacitance measurements, we have shown that the size of the cells treated with dexamethasone were larger than those of the control cells. In addition, treating the cells with 1μmdexamethasone for 48 h increasedl -type Ca2+current density significantly, without affecting the voltage-dependent activation and steady state inactivation of the current. The increase in current density was associated with an elevation of the mRNA transcript encoding thel -type Ca2+channel subunitα1C. Dexamethasone treatment also resulted in an increase in the peak amplitude of the intracellular Ca2+transient measured by fura-2/epifluorescence. Finally, we have demonstrated that the hypertrophic effect of dexamethasone, characterized by the ratio of protein content per cell, was blocked by thel -type specific antagonist, nifedipine. In conclusion, an elevation ofl -type Ca2+current is involved in the process of dexamethasone-induced cardiac myocyte hypertrophy in neonatal rats.
通过电压敏感钙通道调节钙内流对心肌细胞肥大的影响。
影响因子：
5
作者：
S. P. Lubic;K. Giacomini;J. Giacomini
通讯作者：
J. Giacomini
地塞米松对支气管肺发育不良早产儿血压的影响。
影响因子：
3.3
作者：
K. Marinelli;G. Burke;V. Herson
通讯作者：
V. Herson