Effects of beta-carotene and smoking on heart remodeling after myocardial infarction.
OBJECTIVE
To analyze the effects of beta-carotene on the ventricular remodeling process following myocardial infarction (MI) in rats exposed to cigarette smoke.


METHODS
After acute myocardial infarction (AMI), the animals were divided into four groups: 1) Group C, 24 animals that were given standard diet; 2) Group BC, 26 animals that were given beta-carotene; 3) Group ECS, 26 animals that were given standard diet and were exposed to cigarette smoke; and 4) Group BC+ECS, 20 animals that were given beta-carotene and were exposed to cigarette smoke. After six months, a morphofunctional study was performed. We used a 5% significance level.


RESULTS
As regards diastolic areas (DA) and systolic areas (SA), the values for the BC group were higher than those for the C group. If DA/body weight (BW) and SA/BW are considered, the values for group BC+ECS were higher than the values for group C. As regards the fractional area change, we observed significant differences between ECS (lower values) and C (higher values) and between BC (lower values) and C (higher values). Differences between groups regarding infarction size were not observed. The ECS group presented higher values for myocyte cross-section area (MCA) than control animals. Additionally, the BC+ECS group presented higher MCA values than the BC, ECS and C groups.


CONCLUSIONS
After myocardial infarction, smoking and beta-carotene intensified the heart remodeling process; harmful effects of the remodeling process were heightened when the two treatments were used in conjunction.
Zornoff
Leonardo A M
LA
Faculdade de Medicina de Botucatu, Universidade Estadual de São Paulo, Botucatu, SP, Brasil. lzornoff@fmb.unesp.br
Duarte
Daniella R
DR
Minicucci
Marcos F
MF
Azevedo
Paula S
PS
Matsubara
Beatriz B
BB
Matsubara
Luiz S
LS
Campana
Alvaro O
AO
Paiva
Sergio A R
SA
D000704:Analysis of Variance; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D004032:Diet; D019587:Dietary Supplements; D004452:Echocardiography; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D019570:Inhalation Exposure / Q000009:adverse effects*; D008297:Male; D023421:Models, Animal; D009203:Myocardial Infarction / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology*; D009206:Myocardium / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D012907:Smoking / Q000009:adverse effects*; D020257:Ventricular Remodeling / Q000187:drug effects* / Q000502:physiology; D019207:beta Carotene / Q000494:pharmacology*
D000975:Antioxidants; D019207:beta Carotene