Comparative studies of Ca N-acetylhomotaurinate and Ca N-Acetyltaurinate. I: Effects on the ionic transfer through the isolated human amnion

The effects of two taurine and homotaurine derivatives (Ca N-acetyltaurinate : ATACa and Ca N-acetylhomotaurinate : AOTACa) were studied on the ionic transfer through a membranous model : the human isolated amniotic membrane. The ionic transfer was evaluated by measurements of the various components (cellular and paracellular) of the total conductance across the membrane. AOTACa influenced all the components of the total ionic conductance without flux ratio modifications and the general action scheme was a biphasic effect : decrease conductance with low concentrations and increase conductance with high concentrations. This effect might be important in the case of lower or higher supplementation. ATACa only interfered with some conductance components and this action was predominantly monophasic (decreased or increased conductance). This study indicates differential actions between two closely related molecules on a membranous model.