title: Increase of nucleotidase activities in rat blood serum after a single convulsive injection of pentylenetetrazol.
abstract: Adenosine has been shown to be a major regulator in convulsive disorders exerting its anticonvulsant effects on various seizure models. The ectonucleotidase pathway is an important metabolic source of extracellular adenosine. In this study, we evaluated ATP, ADP and AMP hydrolysis in rat serum after a single convulsive injection of pentylenetetrazol (PTZ). The animals were sacrificed at 5 and 30 min, 1, 5, 12, 24 and 48 h after an intraperitoneal injection of PTZ (60 mg/kg). ATP, ADP and AMP hydrolysis by rat blood serum were significantly increased (40-50%) until 24 h after PTZ injection. There were no significant differences in the nucleotide hydrolysis when the in vitro effect of different concentrations of PTZ was analyzed. Changes in nucleotide hydrolysis observed after acute administration of PTZ could not be attributed to phosphodiesterase activity since PTZ-treated rats did not demonstrate significant differences in the hydrolysis of the substrate marker of this enzyme when compared with control rats. These results suggest that the stimulation of the nucleotidase pathway may play an important role in attenuating seizure activity.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Anexo Rua Ramiro Barcelos, 2600-90035-003 Porto Alegre, RS, Brazil.
authors.forename: Alessandra Nejar
authors.initials: AN
authors.lastname: Bruno
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Oses
authors.forename: Carla Denise
authors.initials: CD
authors.lastname: Bonan
authors.forename: Roger
authors.initials: R
authors.lastname: Walz
authors.forename: Ana Maria Oliveira
authors.initials: AM
authors.lastname: Battastini
authors.forename: João José Freitas
authors.initials: JJ
authors.lastname: Sarkis
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D007274:Injections, Intraperitoneal; D009708:Nucleotidases / Q000097:blood*; D010433:Pentylenetetrazole / Q000008:administration & dosage* / Q000009:adverse effects; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000097:blood* / Q000139:chemically induced / Q000201:enzymology
chemical_list: D009708:Nucleotidases; C030287:nucleotidase; D010433:Pentylenetetrazole