title: Pharmacological activity of ruthenium complexes trans-[RuCl(2)(L)4] (l = nicotinic or i-nicotinic acid) on anxiety and memory in rats.
abstract: Many biological properties have been attributed to ruthenium complex I (trans-[RuCl(2)(nic)(4)]) and ruthenium complex II (trans-[RuCl(2 )(i-nic)( 4)]) including nitric oxide synthase inhibition. In this study, we evaluated pharmacological effects of these complexes on anxiety and memory formation. Memory was evaluated with inhibitory avoidance and habituation to an open-field and anxiety was tested with elevated plus-maze. Adult male Wistar rats (250 to 350 g) received intraperitoneal injections of vehicle, ruthenium complex I (45.2, 90.4, or 180.7 mumol/kg), or ruthenium complex II (0.08, 4.5, or 13.6 mumol/kg) 30 min prior open-field training or elevated plus-maze test and 30 min or 0 h after training. No effects were observed in the anxiety parameters and habituation to an open-field. The ruthenium complexes impaired memory retention compared with vehicle group in the inhibitory avoidance, as when administrated 30 min prior as immediately after training. The memory impairment induced by ruthenium complexes may be due to their nitric oxide synthase inhibition capacity.
authors.affiliation: Laboratório de Neurociências, Universidade do Extremo Sul Catarinense, 88806-000, Criciúma, SC, Brazil.
authors.forename: Samira Silva
authors.initials: SS
authors.lastname: Valvassori
authors.forename: Maykon Passos
authors.initials: MP
authors.lastname: Cristiano
authors.forename: Danon Clemes
authors.initials: DC
authors.lastname: Cardoso
authors.forename: Glauco Damiani
authors.initials: GD
authors.lastname: Santos
authors.forename: Márcio Rodrigo
authors.initials: MR
authors.lastname: Martins
authors.forename: João
authors.initials: J
authors.lastname: Quevedo
authors.forename: Marcos Marques
authors.initials: MM
authors.lastname: da Silva Paula
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents; D001362:Avoidance Learning / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000494:pharmacology*; D006185:Habituation, Psychophysiologic / Q000187:drug effects; D007202:Indicators and Reagents; D007274:Injections, Intraperitoneal; D007539:Isonicotinic Acids / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects*; D009539:Nicotinic Acids / Q000494:pharmacology*; D052248:Nitric Oxide Synthase Type I / Q000037:antagonists & inhibitors; D009942:Organometallic Compounds / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D014151:Anti-Anxiety Agents; D004791:Enzyme Inhibitors; D007202:Indicators and Reagents; D007539:Isonicotinic Acids; D009539:Nicotinic Acids; D009942:Organometallic Compounds; C440900:dichlorotetrakis(isonicotinic acid)ruthenium(II); C440899:dichlorotetrakis(nicotinic acid)ruthenium(II); D052248:Nitric Oxide Synthase Type I