title: Effects of structural analogues of nociceptin(1-13)NH₂ on brain antioxidant status in kainic acid-treated rats.
abstract: The in vivo effects of nociceptin (N/OFQ(1-13)NH(2) ) and its structural analogues ([Dab(9) ]N/OFQ(1-13)NH(2) , [Dap(9) ]N/OFQ(1-13)NH(2) and [Cav(9) ]N/OFQ(1-13)NH(2) ) on the levels of lipid peroxidation and cell antioxidants (enzyme and non-enzyme) in brain of control and kainic acid (KA)-treated rats were studied. In control animals, [Dab(9) ]N/OFQ(1-13)NH(2) and [Dap(9) ]N/OFQ(1-13)NH(2) , unlike N/OFQ(1-13)NH(2) and [Cav(9) ]N/OFQ(1-13)NH(2) , slightly increased the brain lipid peroxidation; the rest of the parameters were unchanged by all neuropeptides tested. KA (0.25 µg in 0.5 µl, i.c.v) increased the lipid peroxidation (4 and 24 h after KA-injection) and decreased the glutathione level (1 h after KA-administration). One hour after KA-administration, the neuropeptides (2 µg in 0.5 µl, injected 30 min before KA) showed the following effects: a slight decrease in the KA-induced lipid peroxidation by all nociceptin analogues and an enhancement of the KA-decreased GSH level, but by [Cav(9) ]N/OFQ(1-13)NH(2) only. The brain antioxidant enzyme activities were unchanged in all used experimental groups. In addition, the nociceptin analogues, especially [Can(9) ]N/OFQ(1-13)NH(2) , showed a good antioxidant capacity in chemical systems, generating reactive oxygen species. In conclusion, the substitution of lysin (Lys) in N/OFQ(1-13)NH(2) molecule with other amino acids might contribute to changes in its antioxidant properties. Copyright © 2011 John Wiley & Sons, Ltd.
authors.affiliation: Institute of Neurobiology, Bulgarian Academy of Sciences, 23 Acad. G. Bonchev St., Sofia, Bulgaria.
authors.forename: Elina
authors.initials: E
authors.lastname: Tzvetanova
authors.forename: Galina
authors.initials: G
authors.lastname: Nenkova
authors.forename: Almira
authors.initials: A
authors.lastname: Georgieva
authors.forename: Albena
authors.initials: A
authors.lastname: Alexandrova
authors.forename: Radoslav
authors.initials: R
authors.lastname: Girchev
authors.forename: Margarita
authors.initials: M
authors.lastname: Kirkova
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D007608:Kainic Acid / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D018847:Opioid Peptides / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D000097629:Nociceptin
chemical_list: D000975:Antioxidants; D007608:Kainic Acid; D018847:Opioid Peptides; D000097629:Nociceptin