Sm. Somani et K. Husain, EXERCISE TRAINING ALTERS KINETICS OF ANTIOXIDANT ENZYMES IN RAT-TISSUES, Biochemistry and molecular biology international, 38(3), 1996, pp. 587-595
Michaelis-Menten constant (K-m) and maximum velocity (V-max) of catala
se(CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GR
) in various tissues of exercise-trained old rats were compared with t
he age matched sedentary control. Exercise training increased the maxi
mum velocity (V-max) for CAT in the brain (350%), liver (33%), lung (3
4%), muscle (25%) and testes (21%); for GSH-Px (using t-butyl hydroper
oxide as a substrate) in the liver (22%), lung (25%), and testes (52%)
; for GSH-Px (using GSH as a cosubstrate) in the brain (64%) and liver
(100%), and for GR in testes (50%). This increase in V-max indicates t
he potential activation of these enzymes in the specific tissues. Exer
cise training differentially altered the affinities of enzyme (K-m) fo
r CAT, GSH-Px and GR to their substrates. These studies suggest that e
xercise training provided a beneficial role by activation of antioxida
nt enzymes in specific tissues of aged rats. Thus, exercise training a
ids in coping with oxidative stress in old age.