Jornal de Oftalmologia Clínica e Experimental
Acesso livre

Abstrato

Extracellular Zinc Chelator In Vivo On System Of Taurine in Retina: Transport, Concentrations and Localization of Transporter

Asarí Márquez, Mary Urbina, Manuelita Quintal, Francisco Obregón, Víctor Salazar, Lucimey Lim

Taurine and zinc are relevant molecules in the retina, both are highly concentrated and have similar functions in this structure. Little is known about the mechanisms of action of this amino acid and the interaction with other molecules such as zinc. The objectives of the present study were to evaluate the consequences of zinc deficiency by the extracellular chelator diethylenetriaminepenta-acetic acid (DTPA) on taurine levels, transport and localization of taurine transporter in rat retina. Various concentrations of the extracellular zinc chelator, DTPA, dissolved in dimethylsulfoxide, was administered intraocular: 10, 100, 250 and 500 μM. Retinas were dissected 3, 5 and 10 days later. Zinc was determined by spectrophotometry. Taurine levels, determined by high performance liquid chromatography with fluorescence detection, DTPA administration, 10 μM, decreased taurine in 56% at 3 days. Capacity of taurine transport, using [³H]taurine, was decreased in 44% without changes in the affinity after DTPA. The treatment produced differences in the distribution of taurine transporter in all layers of retina, the least in the outer plexiform layer. The observations contribute to understanding of taurine-zinc interaction in the retina and could have functional implications. The effects of zinc or decrease on the system of taurine, transport, levels and location of the transporter are indicative of functional relevances. They are aspects crucial to the understanding of taurine-zinc interaction in the retina.