Estrogen increases low voltage-activated calcium current density in GH3 anterior pituitary cells.
Estrogen increases low voltage-activated calcium current density in GH3 anterior pituitary cells.
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DOI：
10.1210/endo.132.4.8462461
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发表时间：
1993-04
期刊：
影响因子：
4.8
通讯作者：
A. K. Ritchie
中科院分区：
文献类型：
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作者：
A. K. Ritchie
在垂体前叶细胞系GH 3中检测了雌激素（17 β-雌二醇）对钙电流密度的影响。向生长培养基中添加1 nM雌激素可诱导低电压激活（LVA）Ca 2+电流密度增加4至5倍，而不影响高电压激活的Ca 2+电流密度。24小时后增加是显着的，在3天内达到最高水平，并逆转与类似的时间过程中，雌激素被撤回。雌激素刺激LVA Ca 2+电流密度的EC 50约为30 pM。雌激素诱导的LVA电流具有与对照相似的电压依赖性和激活、失活和失活的时间过程。雌激素的作用需要蛋白质合成，因为它被放线菌酮阻断。这表明雌激素诱导的LVA Ca 2+电流密度的增加可能是由于膜上功能通道数量的增加。这种效应可能是由于插入新的通道或合成一种蛋白质，将预先存在的沉默通道转化为功能通道。
The effects of estrogen (17 beta-estradiol) on calcium current density were examined in the GH3 anterior pituitary cell line. The addition of 1 nM estrogen to the growth medium induces a 4- to 5-fold increase in low voltage-activated (LVA) Ca2+ current density without affecting high voltage-activated Ca2+ current density. The increase is significant after 24 h, reaches a maximum level in 3 days, and reverses with a similar time course when the estrogen is withdrawn. The EC50 for estrogen stimulation of LVA Ca2+ current density is about 30 pM. The LVA current induced by estrogen has similar voltage dependence and time course of activation, inactivation, and deactivation as controls. The effect of estrogen requires protein synthesis, since it is blocked by cycloheximide. It is suggested that the estrogen-induced increase in LVA Ca2+ current density may be due to an increase in the number of functional channels in the membrane. This effect could be due to insertion of new channels or synthesis of a protein that converts preexisting silent channels into functional channels.