The role of oxidative stress and lipid peroxidation in ventricular remodeling induced by tobacco smoke exposure after myocardial infarction.
OBJECTIVE
To evaluate the roles of oxidative stress and lipid peroxidation in the ventricular remodeling that is induced by tobacco smoke exposure after myocardial infarction.


METHODS
After induced myocardial infarction, rats were allocated into two groups: C (control, n=25) and ETS (exposed to tobacco smoke, n=24). After 6 months, survivors were submitted to echocardiogram and biochemical analyses.


RESULTS
Rats in the ETS group showed higher diastolic (C = 1.52 +/- 0.4 mm(2), ETS = 1.95 +/- 0.4 mm(2); p=0.032) and systolic (C = 1.03 +/- 0.3, ETS = 1.36 +/- 0.4 mm(2)/g; p=0.049) ventricular areas, adjusted for body weight. The fractional area change was smaller in the ETS group (C = 30.3 +/- 10.1 %, ETS = 19.2 +/- 11.1 %; p=0.024) and E/A ratios were higher in ETS animals (C = 2.3 +/- 2.2, ETS = 5.1 +/- 2.5; p=0.037). ETS was also associated with a higher water percentage in the lung (C = 4.8 (4.3-4.8), ETS = 5.5 (5.3-5.6); p=0.013) as well as higher cardiac levels of reduced glutathione (C = 20.7 +/- 7.6 nmol/mg of protein, ETS = 40.7 +/- 12.7 nmol/mg of protein; p=0.037) and oxidized glutathione (C = 0.3 +/- 0.1 nmol/g of protein, ETS = 0.9 +/- 0.3 nmol/g of protein; p=0.008). No differences were observed in lipid hydroperoxide levels (C = 0.4 +/- 0.2 nmol/mg of tissue, ETS = 0.1 +/- 0.1 nmol/mg of tissue; p=0.08).


CONCLUSIONS
In animals exposed to tobacco smoke, oxidative stress is associated with the intensification of ventricular remodeling after myocardial infarction.
Duarte
Daniella R
DR
Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, São Paulo State University, Botucatu/SP, Brazil.
Minicucci
Marcos F
MF
Azevedo
Paula S
PS
Matsubara
Beatriz B
BB
Matsubara
Luiz S
LS
Novelli
Ethel L
EL
Paiva
Sergio A R
SA
Zornoff
Leonardo A M
LA
D000818:Animals; D004195:Disease Models, Animal; D004452:Echocardiography; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000378:metabolism / Q000503:physiopathology*; D018384:Oxidative Stress / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012907:Smoking / Q000009:adverse effects*; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling / Q000502:physiology*