%0 Journal Article
%T Lipid peroxidation and total radical-trapping potential of the lungs of rats submitted to chronic and sub-chronic stress
%A Torres
%A R.L.
%A Torres
%A I.L.S.
%A Gamaro
%A G.D.
%A Fontella
%A F.U.
%A Silveira
%A P.P.
%A Moreira
%A J.S.R.
%A Lacerda
%A M.
%A Amoretti
%A J.R.
%A Rech
%A D.
%A Dalmaz
%A C.
%A Bell¨®
%A A.A.
%J Brazilian Journal of Medical and Biological Research
%D 2004
%I Associa??o Brasileira de Divulga??o Cient¨ªfica
%R 10.1590/S0100-879X2004000200004
%X exposure to stress induces a cluster of physiological and behavioral changes in an effort to maintain the homeostasis of the organism. long-term exposure to stress, however, has detrimental effects on several cell functions such as the impairment of antioxidant defenses leading to oxidative damage. oxidative stress is a central feature of many diseases. the lungs are particularly susceptible to lesions by free radicals and pulmonary antioxidant defenses are extensively distributed and include both enzymatic and non-enzymatic systems. the aim of the present study was to determine lipid peroxidation and total radical-trapping potential (trap) changes in lungs of rats submitted to different models of chronic stress. adult male wistar rats weighing 180-230 g were submitted to different stressors (variable stress, n = 7) or repeated restraint stress for 15 (n = 10) or 40 days (n = 6) and compared to control groups (n = 10 each). lipid peroxidation levels were assessed by thiobarbituric acid reactive substances (tbars), and trap was measured by the decrease in luminescence using the 2-2'-azo-bis(2-amidinopropane)-luminol system. chronic variable stress induced a 51% increase in oxidative stress in lungs (control group: 0.037 ¡À 0.002; variable stress: 0.056 ¡À 0.007, p < 0.01). no difference in tbars was observed after chronic restraint stress, but a significant 57% increase in trap was presented by the group repeatedly restrained for 15 days (control group: 2.48 ¡À 0.42; stressed: 3.65 ¡À 0.16, p < 0.05). we conclude that different stressors induce different effects on the oxidative status of the organism.
%K stress
%K tbars
%K trap
%K free radicals
%K lungs
%K oxidative stress.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0100-879X2004000200004&lng=en&nrm=iso&tlng=en