Taurine (2-aminoethane sulphonic acid) is the most abundant amino acid in the heart and contributes approximately 50% of the total amino acid pool. The intracellular concentration of taurine is species dependent, commonly about 5–20 mM1. Intracellular levels are maintained despite a much lower plasma concentration of about 60 µ M2. The sarcoplasmic taurine concentration is linked to that of intracellular sodium suggesting the presence of sarcolemmal Na-taurine co-transport3,4. Elevated taurine levels have been found in heart tissue from patients with congestive heart failure and in experimental models of cardiac hypertrophy5 while the taurine content of the heart decreases as a consequence of ischemia6.