[Comparative effect of pyrazidol and imizin on the ECG and other indices of cardiac activity].

With enteral administration to dogs of equitherapeutic doses (pyrazidol-25 mg/kg, imizin-15 mg/kg) pyrazidol did not provoke myocardial ischemia caused by imizin (imipramin). ECG changes in rats following introduction of pyrazidol and imizin show the latter to call forth more marked upsets on the level of the cardio-vascular system than does pyrazidol. In a concentration of 3-10-6 g/ml the latter lengthens the refractory period of an isolated rabbit's cardiac auricle by 12.6 per cent on an average, while imizin in the same concentration does it by 34 per cent. In acute tests on cats pyrazidol produces a less pronounced hypotension than does imizin.