Sciatic nerve transection increases gluthatione antioxidant system activity and neuronal nitric oxide synthase expression in the spinal cord.
Glutathione (GSH) is a major non-enzymatic antioxidant which is present in all tissues. Its protective actions occur through different pathways such its role as a substrate of antioxidant enzymes, such as glutathione peroxidase (GPx) and glutathione-S-transferase (GST). Nitric oxide (NO) is involved in many physiological processes in the central nervous system, including nociception. In spite of much evidence concerning oxidative and nitrosative stress and neuropathic pain, the exact role of these molecules in pain processing is still unknown. Sciatic nerve transection (SNT) was employed to induce neuropathic pain in rats. Glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activities, glutathione (GSH) content, GSH/GSSG ratio, nitric oxide metabolites (NOx) and neuronal nitric oxide synthase (nNOS) protein expression in the lumbosacral spinal cord were determined. All of these analyses were performed in the SNT and sham groups 1, 3, 7 and 15 days after surgery. There was an increase in GPx activity and in GSH content 3 days after surgery in both sham and SNT groups, but the GSH/GSSG ratio increased only in the SNT group in this time point. nNOS expression was upregulated 7 days post SNT. NOx was detected 1 day after surgery in sham and SNT groups, but at 7 and 15 days, the increase occurred only in SNT animals. These results support the role of the gluthatione system in pain physiology and highlight the involvement of NO as an important molecule related to nociception.
Guedes
Renata Padilha
RP
Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil.
Dal Bosco
Lidiane
L
Araújo
Alex Sander da Rosa
AS
Belló-Klein
Adriane
A
Ribeiro
Maria Flávia Marques
MF
Partata
Wania Aparecida
WA
D000704:Analysis of Variance; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D015153:Blotting, Western; D005978:Glutathione / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D008161:Lumbosacral Region; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D010146:Pain / Q000201:enzymology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012584:Sciatic Nerve / Q000293:injuries*; D013116:Spinal Cord / Q000201:enzymology / Q000378:metabolism*; D013997:Time Factors
D000975:Antioxidants; D009569:Nitric Oxide; D005979:Glutathione Peroxidase; D052248:Nitric Oxide Synthase Type I; D005982:Glutathione Transferase; D005978:Glutathione