MECHANISMS UNDERLYING TAURINE-MEDIATED ALTERATIONS IN MEMBRANE-FUNCTION

Taurine mediates a plethora of membrane-linked effects in excitable ti ssues. To account for these multiple actions, four hypotheses have bee n proposed. One theory is based on the observation that taurine dimini shes the inflammatory response of several cytotoxic oxidants. It is pr oposed that a reduction in the extent of membrane oxidative injury con tributes to these cytoprotective actions. The second theory maintains that alterations in protein phosphorylation may underlie certain effec ts of taurine, particularly its effect on calcium transport. The third hypothesis assumes that the interaction of taurine with the neutral p hospholipids leads to altered membrane calcium binding and function. T he final theory ties the actions of taurine to inhibition of phospholi pid N-methylation and the resulting changes in membrane composition an d structure. While each of these hypotheses has merit, none of them ca n fully explain the membrane actions of taurine. Further studies are r equired to ascertain the importance of each theory.