Sochorová R, Mosnárová A, Huzuláková I
Katedra patologickej fyziológie LFUK, Bratislava.
Bratisl Lek Listy. 1990 Sep;91(9):727-30.
The effect of estradiol, progesterone, and testosterone on calcium ion transport was studied in the rabbit uterus. To investigate the effect of sex hormones on voltage-dependent calcium channels, the isolated uterus was incubated in Ca2(+)-free depolarizing K+ solution. In this solution cumulative dose-response curves to CaCl2 were obtained by increasing the Ca2+ concentration (10(-5)-10(-3) mol.l-1). A decrease of the maximal contractile response to CaCl2 was recorded after in vitro pretreatment with estradiol (1.8 x 10(-5) mol l-1), (6.4 x 10(-1) mol) and testosterone (5.8 x 10(-5) mol.l-1). The pD2 values were unchanged. The possibility of affecting calcium ion release from intracellular stores by sex hormones was observed indirectly on using Ca2(+)-free Tyrode's solution with 0.8 nmol EDTA. Contractile responses of the isolated uterus were induced by single application of norepinephrine (NE) in the dose of 2 x 10(-4) mol.l-1. Pretreatment with sex hormones decreased the contractile responses of the uterus to NE. The obtained results suggest an important involvement of calcium ions in the mechanism of action of sex hormones upon the myometrial smooth muscle.
在兔子宫中研究了雌二醇、孕酮和睾酮对钙离子转运的影响。为了研究性激素对电压依赖性钙通道的作用，将离体子宫置于无钙的去极化钾溶液中孵育。在此溶液中，通过增加钙离子浓度（10⁻⁵ - 10⁻³ mol·l⁻¹）获得氯化钙的累积剂量 - 反应曲线。用雌二醇（1.8×10⁻⁵ mol·l⁻¹）、孕酮（6.4×10⁻¹ mol）和睾酮（5.8×10⁻⁵ mol·l⁻¹）进行体外预处理后，记录到对氯化钙的最大收缩反应降低。pD2值未改变。在使用含0.8 nmol EDTA的无钙台氏液时，间接观察到性激素影响细胞内钙库释放钙离子的可能性。通过单次应用剂量为2×10⁻⁴ mol·l⁻¹的去甲肾上腺素（NE）诱导离体子宫的收缩反应。性激素预处理降低了子宫对NE的收缩反应。所得结果表明钙离子在性激素对子宫肌层平滑肌的作用机制中起重要作用。
