Age-related changes in reactive oxygen species production in rat brain homogenates.
Neurotoxicol Teratol
; 22(2): 175-81, 2000.
Article
em En
| MEDLINE
| ID: mdl-10758346
ABSTRACT
The generation of reactive oxygen species (ROS) and resultant oxidative stress have been implicated in the mechanism of brain dysfunction due to age-related neurodegenerative diseases or exposure to environmental chemicals. We have investigated intrinsic age-related differences in the ability of the various brain regions to generate ROS in the absence and presence of Fe(2)+. ROS production in crude brain homogenates from adult rats was linear with respect to time and tissue concentration, and was stimulated to a greater extent by Fe(2)+ than was TBARS production. ROS production was then determined in homogenates from cerebral cortex, striatum, hippocampus, and cerebellum of 7-day-old, 14-day-old, 21-day-old, adult (3-6-month old), and aged (24-month-old) rats using the fluorescent probe 2',7'-dichlorodihydrofluorescin (DCFH). Basal levels of ROS production were similar in 7-, 14-, and 21-day olds, increased in adults, and highest in aged rats, and did not differ between brain regions. ROS production was stimulated by Fe(2)+ (0. 3-30 microM) in a concentration-dependent manner in all brain regions. However, the stimulation of ROS production by Fe(2)+ varied with age. ROS production was greater in 14- and 21-day-old rats compared with adult and aged animals. ROS production in 7-day-old rats was decreased at low Fe(2)+ concentrations and increased at high Fe(2)+ concentrations compared to adult and aged rats. These data show that brain homogenates from neonatal rats respond differently to Fe(2)+, and suggest that developing animals may be more sensitive to oxidative stress in the brain after exposure to toxicants. Published by Elsevier Science Inc.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Encéfalo
/
Envelhecimento
/
Peroxidação de Lipídeos
/
Espécies Reativas de Oxigênio
Limite:
Animals
Idioma:
En
Ano de publicação:
2000
Tipo de documento:
Article