Excretion of taurine during healing of experimental wounds.

HE INVESTIGATION of the excretion of free amino acids after burnB and surgery in humans (1-6) has given rise to conflicting results. The discrepancies reported quite probably have three principal causes: (1) inadequately controlled observations; (2) comparison of observations from widely disparate environments; and (3) the use of relatively semiquantitative technic for determining amino acids, leading to results that may be easily misinterpreted. A further source of confusion may have been the lack of appreciation by most investigators of the alteration of sulfur amino acid metabolism that occurs after trauma. The metabolism of the sulfur amino acids has been shown to be intimately connected with the processes involved in the regeneration of tissue in wounds (7-10). Although a negative nitrogen balance appears after wounding, the amount of sulfur excreted is not usually commensurate with the nitrogen output when compared to the situation in normal animals. Since taurine represents a large part of the total amino acids excreted, changes in sulfur metabolism might be expected to have a notable influence on the level of the total amino acids in the urine. The level and quality of protein nutrition (11) may be another factor of considerable influence in the excretion of amino acids after wounding. In this paper are reported the results of a comparison of the excretion of amino acid nitrogen and taurine by normal and by wounded rats on a high-protein and on a proteinfree diet.