Oxidative damage in substantia nigra and striatum of rats chronically exposed to ozone.
The purpose of this work was to study if chronic low-dose ozone exposure could per se induce oxidative damage to neurons of striatum and substantia nigra. Thirty male Wistar rats were divided into three groups--Group 1: exposed to an air stream free of ozone; Group 2: exposed for 15 days to ozone; Group 3: exposed for 30 days to ozone. Ozone exposure was carried out daily for 4 h at a 0.25 ppm dose. Each group was then tested for (1) motor activity, (2) quantification of lipid peroxidation levels, (3) Klüver-Barrera staining, and (4) immunohistochemistry for tyrosine hydroxylase (TH), dopamine and adenosine 3',5'-monophosphate-regulated phosphoprotein of 32 kD (DARPP-32), inducible nitric oxide synthase (iNOS), and superoxide dismutase (SOD), to study neuronal alterations in striatum and substantia nigra. Results indicate that ozone exposure causes a significant decrease in motor activity. Ozone produced lipid peroxidation, morphological alterations, loss of fibers and cell death of the dopaminergic neurons. The DARPP-32, iNOS and SOD expression increased with repetitive ozone exposure. These alterations suggest that ozone causes oxidative stress which induces oxidative damage to substantia nigra and striatum of the rat.
Pereyra-Muñoz
Naira
N
Physiology Department, Faculty of Medicine, National Autonomous University of Mexico, CP 04510, AP 70-250, Mexico-City, Mexico.
Rugerio-Vargas
Concepción
C
Angoa-Pérez
Mariana
M
Borgonio-Pérez
Gabino
G
Rivas-Arancibia
Selva
S
D000465:Algorithms; D000818:Animals; D002452:Cell Count; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32 / Q000378:metabolism; D007150:Immunohistochemistry; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D017072:Neostriatum / Q000187:drug effects / Q000473:pathology*; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D010083:Oxidants, Photochemical / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D010126:Ozone / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D013378:Substantia Nigra / Q000187:drug effects / Q000473:pathology*; D013482:Superoxide Dismutase / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D010083:Oxidants, Photochemical; C497930:Ppp1r1b protein, rat; D010126:Ozone; D052247:Nitric Oxide Synthase Type II; D014446:Tyrosine 3-Monooxygenase; D013482:Superoxide Dismutase