Alterations in glutathione levels of brain structures caused by acute restraint stress and by nitric oxide synthase inhibition but not by intraspecific agonistic interaction.
Glutathione is the major non-protein thiol to which many different roles in the central nervous system (CNS) are attributed. To further investigate the glutathione response in the CNS, we tested the effect of three stress models on glutathione levels in the brain. We tested the effect of two models of repeated intraspecific agonistic interaction in mice. No influence was observed over the glutathione levels in the mice cerebral cortex, cerebellum, liver, and blood. Acute restraint stress in rats was found to induce an increase in glutathione levels in the cerebellum after 2 and 4 h of immobilization, an effect not observed in the cerebral cortex, striatum, and hippocampus. To investigate the interference of an inhibitor of nitric oxide synthase (NOS), N(omega)Nitro-L-arginine-methyl-ester (L-NAME, 50 mg/kg) was applied i.p. at the beginning of restraint stress. L-NAME alone did not lead to a change in glutathione levels although, in combination with restraint stress, it induced an increase in such levels. This effect was observed in all four structures studied, i.e. cortex, hippocampus, striatum, and cerebellum. The values returned to basal levels after 6h of immobilization. In conclusion, the pattern of dominance, after repeated intraspecific agonistic interaction, was ineffective in producing alterations in brain glutathione, whereas acute restraint stress led to an increase in glutathione levels within a window of 2-4 h, and the inhibition of NOS increased glutathione levels in all studied rat brain structures, suggesting a specificity interference of acute restraint stress with the glutathione system.
Ghizoni
Daniel Mathias
DM
Departamento de Ciências Fisiológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC, Brazil.
Pavanati
Kelly Cristine Alves
KC
Arent
André Mendes
AM
Machado
Claudia
C
Faria
Moacir Serralvo
MS
Pinto
Cristina Maria Henrique
CM
Gasparotto
Odival Cezar
OC
Gonçalves
Sonia
S
Dafre
Alcir Luiz
AL
D000378:Agonistic Behavior / Q000187:drug effects / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D001921:Brain / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism*; D008297:Male; D051379:Mice; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical / Q000379:methods; D013312:Stress, Physiological / Q000378:metabolism*
D019001:Nitric Oxide Synthase; D005978:Glutathione; D019331:NG-Nitroarginine Methyl Ester