title: Involvement of Na+/H+ exchanger in the calcium signaling in epimastigotes of Trypanosoma cruzi.
abstract: We studied the effect of Na(+) extracellular on Ca(2+) mobilization from intracellular store evoked by carbachol in Trypanosoma cruzi. We report that slow component of Ca(2+) signaling evoked by agonist is dependent on extracellular Na(+) but not on InsP(3) increase. Moreover, this Ca(2+) signaling progressively increased when pH of the medium changed from 7.0 to 7.8. In addition, we found that it was regulated by PKC. The agonist was also able to induce the alkalinization of the acidic compartment, and both Ca(2+) signaling and alkalinization were inhibited by the EIPA-inhibitor of the Na(+)/H(+) exchanger. These results demonstrated the alkalinization of acidic vacuoles and PKC are involved in the triggering of the epimastigote Ca(2+) signaling.
authors.affiliation: Química Biológica, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, 5800 Río Cuarto, Córdoba, Argentina.
authors.forename: Mariana
authors.initials: M
authors.lastname: Bollo
authors.forename: Sergio
authors.initials: S
authors.lastname: Bonansea
authors.forename: Estela E
authors.initials: EE
authors.lastname: Machado
mesh_terms: D000584:Amiloride / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling; D006863:Hydrogen-Ion Concentration; D019831:Sodium-Calcium Exchanger / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014349:Trypanosoma cruzi / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D019831:Sodium-Calcium Exchanger; D000584:Amiloride; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium; C039614:ethylisopropylamiloride