[The enzymatic activity of adenosine metabolism in the rat heart. The effects of cardiac hypertrophy].

The transmural distribution of the adenosine metabolizing enzyme activities 5'nucleotidase (5'N) and adenosine deaminase (ADA) across the left ventricular wall was explored in rats with heart hypertrophy induced by aortocaval shunt (FAC), or coarctation of the abdominal aorta (S) or by tireotoxicosis (T). FAC caused largest heart hypertrophy with a very short latency (1 day: + 0%, 3.5 days: + 30%, 7 days: + 41%, 21 days: + 49%). A 30% increase in the left ventricle free wall was observed after 3.5, 14 or 28 days of treatment with FAC, T or S respectively. Different changes in enzyme levels and alteration of transmural distribution profiles were observed with the different types of heart hypertrophy. Level of 5'N was decreased with FAC, did not change with T and increased with S; levels of ADA were always increased. The pattern of the transmural distribution of 5'N was affected by S but not by T and FAC, whereas distribution of ADA was not affected by S and T and was altered by FAC transiently.