Quinolinic acid as calcium channel modulator in isolated rat heart preparations

The effect of quinolinic acid perfusion on isolated rat hearts according to the procedure of Langendorff was studied. In the experiments when the final concentration range of quinolinic acid decreased from 10(-1) to 10(-7) mol/l through intermediate concentrations, a negative inotropic response with the enhancement of the coronary flow was stated. When an isolated heart preparation was perfused with 4 x 10(-3) and 4 x 10(-4) mol/l of a quinolinic acid, a biphasic response of the contractility was visible. In the experiments initial increase and then decrease in the contractility were demonstrated. Therefore, these effects of quinolinic acid were similar to those of the well-known action of the classical calcium channel modulators and may remain the basis of quinolinic acid neuro-excitotoxing activity after intracerebral and general treatment.