title: Trypanosoma cruzi: participation of intracellular Ca2+ during metacyclic trypomastigote-macrophage interaction.
abstract: The interaction between Trypanosoma cruzi, the protozoan causative of Chagas's disease, and its host cell is a complex process in which multiple signals including those of Ca2+ are involved. Macrophage cytosolic Ca2+ levels were studied during the interaction of these cells with metacyclic trypomastigotes of T. cruzi, since this event is an initial step in the natural infection. In this model we detected an increase in the macrophage cytosolic Ca2+ concentration after infection, or incubation with a metacyclic lysate or with isolated membranes, suggesting that these increments could be necessary for parasite invasion. This fact was confirmed by treating macrophages with a Ca2+ chelator or a Ca2+ channel antagonist which decreased the infection percentages while parasitization levels increased after treatment with Ca2+ channel agonist.
authors.affiliation: Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, Argentina.
authors.forename: S E
authors.initials: SE
authors.lastname: Wilkowsky
authors.forename: M J
authors.initials: MJ
authors.lastname: Wainszelbaum
authors.forename: E L
authors.initials: EL
authors.lastname: Isola
mesh_terms: D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D002614:Chelating Agents / Q000494:pharmacology*; D003600:Cytosol / Q000378:metabolism; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D005456:Fluorescent Dyes; D016257:Fura-2 / Q000031:analogs & derivatives; D005711:Gallopamil / Q000494:pharmacology; D006790:Host-Parasite Interactions; D015759:Ionomycin / Q000494:pharmacology; D007700:Kinetics; D008264:Macrophages / Q000187:drug effects / Q000469:parasitology* / Q000502:physiology; D013050:Spectrometry, Fluorescence; D013997:Time Factors; D014349:Trypanosoma cruzi / Q000472:pathogenicity / Q000502:physiology*
chemical_list: D002614:Chelating Agents; D005456:Fluorescent Dyes; C049925:fura-2-am; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D005711:Gallopamil; D004533:Egtazic Acid; D015759:Ionomycin; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D002118:Calcium; D016257:Fura-2