Balaraman R, Rathod S P, Gulati O D
Pharmacy Department, Faculty of Technology & Engineering, M.S. University of Baroda, India.
Indian J Exp Biol. 1990 May;28(5):455-9.
In rat isolated aorta low concentration of CdCl2 (4.8 x 10(-8) M) produced a significant increase in pD2 value of KCl and noradrenaline (NA) with an increase in the maxima, while higher concentration of CdCl2 (1.44 x 10(-5) M) produced a significant rightward shift of the dose-response curve with a depression of maxima. In rat isolated portal vein 4.8 x 10(-7) M CdCl2 produced a significant increase in the pD2 value of KCl with an increase in the maxima, while higher concentration of CdCl2 (4.8 x 10(-5) M) produced a significant rightward shift of the dose-response curve of KCl and NA with a depression of maxima. In rat isolated vas deferens and anococcygeus muscle 4.8 x 10(-8) M CdCl2 produced a significant increase in pD2 value of KCl with an increase in the maxima, while higher concentrations of CdCl2 (4.8 x 10(-6) M and 1.44 x 10(-5) M) produced a significant rightward shift of the dose-response curve of KCl and NA. It is suggested that enhancement and reduction of response to KCl and NA, in presence of different concentrations of CdCl2 might be due to the alteration in the fluxes of calcium ion since these spasmogens produce their action by increasing the availability of calcium ions for the contractile machinery.
在大鼠离体主动脉中，低浓度的氯化镉（4.8×10⁻⁸ M）使氯化钾和去甲肾上腺素（NA）的pD2值显著增加，最大值也增加；而高浓度的氯化镉（1.44×10⁻⁵ M）使剂量-反应曲线显著右移，最大值降低。在大鼠离体门静脉中，4.8×10⁻⁷ M氯化镉使氯化钾的pD2值显著增加，最大值增加；而高浓度的氯化镉（4.8×10⁻⁵ M）使氯化钾和NA的剂量-反应曲线显著右移，最大值降低。在大鼠离体输精管和肛尾肌中，4.8×10⁻⁸ M氯化镉使氯化钾的pD2值显著增加，最大值增加；而高浓度的氯化镉（4.8×10⁻⁶ M和1.44×10⁻⁵ M）使氯化钾和NA的剂量-反应曲线显著右移。有人认为，在不同浓度氯化镉存在的情况下，对氯化钾和NA反应的增强和减弱可能是由于钙离子通量的改变，因为这些致痉剂通过增加收缩机制可利用的钙离子来发挥作用。
