title: Anxiogenesis induced by nitric oxide synthase inhibition and anxiolytic effect of melanin-concentrating hormone (MCH) in rat brain.
abstract: In this study, the involvement of nitric oxide (NO) in the mechanism of anxiety was investigated. The rats received an intraamygdaline or intrahippocampal injection of the nitric oxide synthase inhibitor, N(G)-nitro-l-arginine (L-NOARG), and were then tested in the plus-maze test. L-NOARG induced a decrease in the time spent by rats in the open arms. Conversely, the administration of the melanin-concentrating hormone (MCH) into these structures increased the number of entries into the open arms as well as the time spent on them. MCH injected in rats pretreated with L-NOARG also was able to revert the anxiogenic effects of L-NOARG in amygdala.
authors.affiliation: Laboratorio de Fisiología, Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba (UNC), 5000 Córdoba, Argentina. fisiol@mail.fcq.unc.edu.ar
authors.forename: M E
authors.initials: ME
authors.lastname: Monzón
authors.forename: M M
authors.initials: MM
authors.lastname: Varas
authors.forename: S R
authors.initials: SR
authors.lastname: De Barioglio
mesh_terms: D000679:Amygdala / Q000187:drug effects / Q000201:enzymology; D000818:Animals; D001921:Brain / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology; D007028:Hypothalamic Hormones / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008543:Melanins / Q000494:pharmacology*; D009389:Neovascularization, Pathologic; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D019335:Nitroarginine / Q000494:pharmacology; D010100:Oxygen / Q000378:metabolism*; D010907:Pituitary Hormones / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D004791:Enzyme Inhibitors; D007028:Hypothalamic Hormones; D008543:Melanins; D010907:Pituitary Hormones; D019335:Nitroarginine; D009569:Nitric Oxide; C019463:melanin-concentrating hormone; D019001:Nitric Oxide Synthase; D010100:Oxygen