Silva de Sá M F, Meirelles R S
Acta Physiol Lat Am. 1978;28(4-5):209-13.
The action of calcium on human umbilical artery was studied by an in vitro perfusion method. An increase in tonus and intense spontaneous activity were observed in the preparations at high calcium concentrations. A marked relaxation of the umbilical artery occurred in the absence of calcium. Estriol had a relaxing effect on the umbilical vessels which was more intense at calcium concentrations near physiological levels. Estriol also abolished spontaneous contractions. In the absence of calcium, estriol showed no relaxing effect. The results suggest a participation of calcium in the mechanism of action of estriol on human umbilical artery in vitro.
采用体外灌注法研究了钙对人脐动脉的作用。在高钙浓度下，观察到标本的张力增加和强烈的自发活动。在无钙情况下，脐动脉出现明显舒张。雌三醇对脐血管有舒张作用，在接近生理水平的钙浓度时作用更强。雌三醇还可消除自发收缩。在无钙情况下，雌三醇无舒张作用。结果提示钙参与了雌三醇在体外对人脐动脉的作用机制。
