[Catecholamine concentration and metabolism in old age]

As shown by examination in apparently healthy persons aged from 20 to 100 years and in experiments on 1--28-month-old albino rats there was a significant change with the progress of age in the content and ratio of catecholamines in the blood, various organs and the urine. The blood noradrenaline level fell considerably; Na/A coefficient also dropped sharply. Catecholamine content in the organs changed irregularly: in the kidneys it increased, in the skeletal muscles--remained unchanged, in the adrenal glands, the heart, the spleen and the liver--decreased. There was a significant reduction with the progress of age of the urinary excretion of adrenaline, noradrenaline, DOPA and vanilyl-amygdalic acid. Elemination of the intravenously injected noradrenaline from the blood of old rats was markedly delayed in comparison with that in the young animals. Depression of the COMT activity did not alter the noradrenaline level in the heart of adult and old rats. Administration of ipraside caused an increase in noradrenaline content in the heart of old rats, but failed to alter it in adult animals. It is suggested that in the catecholamine metabolism of old animals prevalence is given to the processes of oxidative desamination.