[Certain nitrogen-containing components of the heart, of the coronary-sinus blood and of the aorta in experimental myocardial infarct].

Forty-two dogs were subjected to studies of nitrogen-containing metabolites in the blood of the aorta, coronary sinus and in various parts of the heart under normal conditions and 1, 24 hours and 3 days following the induction of myocardial infarction. In normal dogs the myocardium usually retains from the in-flowing blood such components as urea, glutamine, RNA, non-organic phosphates, while the arterio-venous gradient of ammonium, DNA and nucleases is close to zero. The ligation of the coronary sinus is followed by a deceleration of urea formation in the liver, the amount of urea formation in the liver, the amount of urea in the arterial blood and myocardium decreases, the latter, instead of retaining it, throwing it out into the coronary sinus. Like in normal cases, in this pathology the heart muscle is capable of synthesizing urea from ammonium. The infarctized heart actively retains glutamine from blood using it in situ, and does not increase the secretion of free ammonium into the coronary sinus. The level of nucleic acids and the activity of the nucleases significantly increase in the diseased tissue, undergoing no important changes in the blood circulating in the cardiac vessels.