新型正性肌力活性物PHR0007对离体蟾蜍心肌收缩力的影响

Effects of a novel positive inotropic agent PHR0007 on the contractile force of the isolated cardiac muscle in toads

[目的]观察和探讨新型正性肌力活性物PHR0007（三唑并二氢喹啉衍生物）对离体蟾蜍心肌收缩力的影响及其机制．[方法]单用PHR0007（1，3，10μmol／L，1mL／只）、米力农（10μmol／L，1mL／只）、合用PHR0007（10μmol／L）和米力农（10μmol／L）以及追加20g／L氯化钙溶液（30μL）灌注给予离体蟾蜍心脏后，观察心肌收缩力的变化情况．[结果]与空白对照比较，在PHR0007浓度在1～10μmol／L范围内时心肌收缩力增加1．28～1．35倍，并与剂量成正比（r=0．941），单用米力农使心肌收缩力增加1．39倍，合用米力农和PHR0007使心肌收缩力增加1．42倍，追加20g／L氯化钙使心肌收缩力增加1.73倍．[结论]PHR0007具有正性肌力作用，其机制可能与米力农相似或相同．

OBJECTIVE To investigate the effects of PHR 0007 （[-1,2,4] triazolo [4,3-a] quinoline derivative） on the contractile force of the isolated toad＇s cardiac muscles. METHODS Isolated toad hearts were infused with the single doses of PHR 0007 （1, 3 or 10μmol/L, 1 mL of each） and a single dose of milrinone （10μmol/L, 1 mL of each）, or in combination of PHR 0007 （10μmol/L） with milrinone （10 μmol/L）, followed with 20 g/L calcium chloride（30 μL）, and the contractile force, heart rate, and rhythm of the toad＇s cardiac muscles were detected with tension transducer which was connected with BL-420 biological function processing system. RESULTS PHR 0007 increased the contractile force of the toad＇s cardiac muscles. Compared to the control, PHR 0007 at the concentration between 1 9mol/L and 10/zmol/L increased the contractile force 1.28 - 1.35-fold concentration-dependently （r = 0. 941）, and 1/xmol/L of milrinone also increased the contractile force to 1.39-fold. Combination of PHR 0007 with milrinone increased the contractile force only to 1.42-fold, which was not enhanced significantly than the single dose of PHR 0007 or milrinone. But the addition of calcium chloride elevated to 1.73-fold, which was 1.21-fold higher than the combination. CONCLUSION PHR 0007 enhance the contractile force of the isolated toad＇s cardiac muscle without disturbance of the heart rate and rhythm. The positive inotropic mechanism of PHR 0007 may be the same as that of milrinone.