title: Trichomonas vaginalis: cytochemical localization of a NTPDase1 and an ecto-5'-nucleotidase and effects of adenine nucleotides on cellular viability.
abstract: Nucleoside triphosphate diphosphohydrolase 1 (NTPDase1), which hydrolyzes extracellular ATP and ADP, and ecto-5'-nucleotidase, which hydrolyzes AMP, are characterized for Trichomonas vaginalis. Ultrastructural cytochemical microscopy showed NTPDase1 and ecto-5'-nucleotidase activities on the surface of the parasites. High levels of extracellular adenine nucleotides and adenosine did not exert cytolytic effects in intact cells of T. vaginalis. Our results suggest that these enzymes are relevant for the survival of the parasite during exposure to extracellular nucleotides. Since the ecto-localization of these enzymes is essential for the maintenance of adenosine extracellular levels, this nucleoside could be important for the purine salvage pathway in the parasite.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-Anexo, Porto Alegre, Brazil.
authors.forename: Tiana
authors.initials: T
authors.lastname: Tasca
authors.forename: Carla D
authors.initials: CD
authors.lastname: Bonan
authors.forename: Geraldo A
authors.initials: GA
authors.lastname: De Carli
authors.forename: João J F
authors.initials: JJ
authors.lastname: Sarkis
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism*; D000225:Adenine / Q000494:pharmacology; D000227:Adenine Nucleotides / Q000494:pharmacology; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D001081:Apyrase; D004305:Dose-Response Relationship, Drug; D006651:Histocytochemistry / Q000379:methods*; D008136:Longevity / Q000187:drug effects; D008854:Microscopy, Electron; D014246:Trichomonas vaginalis / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure
chemical_list: D000227:Adenine Nucleotides; D015703:Antigens, CD; D015720:5'-Nucleotidase; D000251:Adenosine Triphosphatases; D001081:Apyrase; C067869:CD39 antigen; D000225:Adenine