Sn. Allo et al., TAURINE DEPLETION, A NOVEL MECHANISM FOR CARDIOPROTECTION FROM REGIONAL ISCHEMIA, American journal of physiology. Heart and circulatory physiology, 42(4), 1997, pp. 1956-1961
Three processes that have been implicated in ischemic injury are impai
red Ca2+ movement, altered osmoregulation, and membrane remodeling. Be
cause the amino acid, taurine, affects all three processes, it seemed
logical that changes in the myocardial content of taurine might affect
ischemic injury. To test this hypothesis, infarct size and areas at r
isk were compared in isolated hearts from control and taurine-depleted
rats after a 45-min Ligation of the left anterior descending coronary
artery and 2 h of reperfusion. Hearts of rats treated for 4 wk. with
the taurine inhibitor, beta-alanine, exhibited a 57% reduction in the
infarct size-to-risk area ratio. The degree of cardioprotection was fo
und to correlate (r = 0.85) with the extent of taurine depletion, the
latter dependent on the length of beta-alanine feeding. When the tauri
ne-depleted rats were fed taurine, myocardial taurine levels were rest
ored and the cardioprotection was lost. However, addition of neither b
eta-alanine (3%) nor taurine (20 mM) to the perfusion medium altered i
nfarct size. We conclude that taurine depletion renders the heart resi
stant to injury caused by regional ischemia.