Effects of adenosine on action potentials in the oyster heart, with special reference to the activity of adenosine aminohydrolase

Abstract

1. 1. An exicised piece of heart auricle from Crassostrea nippona Seki was not affected by adenosine (10 −2 M) in acidified sea water (pH 5·0 and 6·4) when studied oscillographically, whereas it was affected at pH 8·1 and 9·4. 2. 2. Adenosine aminohydrolase with optimum at pH 4·5 was found in the heart and was considered to reduce toxicity of adenosine at lower pH's.