Abstract
In order to study the significance of the myocardial ammonia, the coronary arteriovenous differences of ammonia, amide-nitrogens and carbohydrates were deter-mined in normal mongrel dogs under some conditions. From the results obtained by ammonia administration, ammonia was shown to have an unfavorable influence on the carbohydrate metabolism, and the myocardial release of ammonia, glutamic acid and glutamine, and the extraction of α-ketoglutarate were observed. While during intraaortic balloon load, glutamic acid and glutamine tended to be extracted into the myocardium, and ammonia and α-ketoglutarate were released. It is suggested from the present study that glutamic acid and glutamine are important metabolites as nitrogen-rich storage and mobile reserves in the myocardium.
