钙浓度变化和维拉帕米对乙醇对猫乳头肌心脏抑制作用的影响。

Influences of changes in calcium concentration and verapamil on the cardiac depressant effect of ethanol in cat papillary muscle.

Martinez J L, Penna M

Department of Pharmacology, Faculty of Medicine, University of Chile, Santiago.

Gen Pharmacol. 1992 Nov;23(6):1051-6. doi: 10.1016/0306-3623(92)90285-r.

Abstract

In isolated cat heart papillary muscle electrically driven at a constant rate the depressant effects of increasing concentrations of ethanol on peak tension developed (PTD) was studied in Ringer-Locke solution with different calcium concentrations and with the addition of verapamil. 2. Ethanol induced a concentration dependent decrease in PTD that was significantly greater for each concentration of ethanol in hypocalcic medium (1.1 mM) than in normocalcic medium (2.2 mM). 3. In normocalcic (2.2 mM) medium, verapamil (5.1 x 10(-4) mM) plus ethanol (48.6 and 97.2 mM) produced a decrease in PTD to values significantly greater than those obtained by the addition of ethanol and verapamil alone. Therefore a potentiation of the effects of ethanol by verapamil was observed when both drugs act simultaneously. 4. In hypercalcic medium (4.4 mM), verapamil plus ethanol (48.6 and 97.2 mM) produced a slight decrease in PTD that was significantly less than that observed in normocalcic and hypocalcic mediums. 5. In hypocalcic medium (1.1 mM) verapamil plus ethanol (48.6 and 97.2 mM) produced a decrease in PTD that was of the same relative magnitude (%) as that observed in normocalcic medium. However no potentiation of the combined effects of verapamil plus ethanol was observed in hypocalcic medium.

摘要

在以恒定速率电驱动的离体猫心脏乳头肌中，于不同钙浓度的林格-洛克溶液中并添加维拉帕米，研究了乙醇浓度增加对所产生的峰值张力（PTD）的抑制作用。2. 乙醇导致PTD呈浓度依赖性降低，在低钙培养基（1.1 mM）中，每种乙醇浓度下的降低幅度均显著大于正常钙培养基（2.2 mM）中的降低幅度。3. 在正常钙（2.2 mM）培养基中，维拉帕米（5.1×10⁻⁴ mM）加乙醇（48.6和97.2 mM）使PTD降低至显著高于单独添加乙醇和维拉帕米时所获得的值。因此，当两种药物同时作用时，观察到维拉帕米增强了乙醇的作用。4. 在高钙培养基（4.4 mM）中，维拉帕米加乙醇（48.6和97.2 mM）使PTD略有降低，显著低于在正常钙和低钙培养基中观察到的降低幅度。5. 在低钙培养基（1.1 mM）中，维拉帕米加乙醇（48.6和97.2 mM）使PTD降低的相对幅度（%）与在正常钙培养基中观察到的相同。然而，在低钙培养基中未观察到维拉帕米加乙醇联合作用的增强。