Mironneau J, Gargouil Y M
Eur J Pharmacol. 1979 Jul 15;57(1):57-67. doi: 10.1016/0014-2999(79)90103-1.
The effects of indapamide on electrophysiological and mechanical parameters of longitudinal smooth muscle strips isolated from mammalian portal vein were studied by means of a double sucrose gap method associated with a photoelectric device for recording contraction. Indapamide (10(-4) M) reduced both the amplitude of the action potential and the contraction. The calcium inward current decreased and consequently the phasic contraction was also reduced. The potassium outward current was diminished while the tonic contraction was not modified significantly. The depressant nature of the indapamide response could counterbalance the stimulating action of angiotensin II but not that of noradrenaline. The results suggest that indapamide acts primarily on the plasma membrane of vascular smooth muscle by reducing the transmembrane calcium current, although a secondary decrease in the intracellular bound calcium could not be completely excluded.
采用双蔗糖间隙法结合光电装置记录收缩，研究了吲达帕胺对从哺乳动物门静脉分离的纵向平滑肌条电生理和力学参数的影响。吲达帕胺（10⁻⁴ M）降低了动作电位的幅度和收缩。钙内向电流减少，因此相性收缩也减少。钾外向电流减小，而紧张性收缩无明显改变。吲达帕胺反应的抑制性质可抵消血管紧张素II的刺激作用，但不能抵消去甲肾上腺素的刺激作用。结果表明，吲达帕胺主要通过减少跨膜钙电流作用于血管平滑肌的质膜，尽管不能完全排除细胞内结合钙的继发性减少。
