Effect of sexual steroids on the calcium content of aortic atherosclerotic plaque of oophorectomized rabbits
Braz. j. med. biol. res
; 38(5): 705-711, May 2005. tab, graf
Article
em En
| LILACS
| ID: lil-400951
Biblioteca responsável:
BR1.1
ABSTRACT
We determined the effect of conjugated equine estrogen plus medroxyprogesterone acetate on calcium content of aortic atherosclerotic lesions in oophorectomized adult New Zealand rabbits submitted to a cholesterol rich diet. Five groups of 10 animals each were studied G1 = control, G2 = cholesterol diet only, G3 = diet plus conjugated equine estrogen (0.625 mg/day); G4 and G5 = diet, conjugated equine estrogen (0.625 mg/day) plus medroxyprogesterone acetate (5 and 10 mg/day, respectively). Mean weight varied from 2.7 ± 0.27 to 3.1 ± 0.20 kg (P = 0.38) between groups at the beginning and 3.1 ± 0.27 to 3.5 ± 0.20 kg (P = 0.35) at the end of the experiment. Cholesterol and triglyceride levels were determined at the time of oophorectomy, 21 days after surgery (time 0), and at the end of follow-up of 90 days. The planimetric method was used to measure plaque and caryometric method for histopathologic examination of the aorta. Calcium content was determined by the method of von Kossa. A similar increase in cholesterol occurred in all treated groups without differences between them at the end of the study. Groups G4 and G5 had smaller areas of atherosclerotic lesions (2.33 ± 2.8 and 2.45 ± 2.1 cm², respectively) than the groups receiving no progestogens (G2 5.6 ± 4 and G3 4.6 ± 2.8 cm²; P = 0.02). The relation between lesion area and total aorta area was smaller in groups treated with combined drugs compared to the groups receiving no progesterone (G4 14.9 ± 13 and G5 14.2 ± 13.4 vs G2 35.8 ± 26 and G3 25 ± 8 cm², respectively; P = 0.017). Oral conjugated equine estrogen (0.625 mg/day) plus medroxyprogesterone acetate (5 or 10 mg/day) provoked a greater reduction in atherosclerotic plaque area and calcium content in treated groups, suggesting a dose-dependent effect.
Texto completo:
1
Base de dados:
LILACS
Assunto principal:
Aorta
/
Arteriosclerose
/
Cálcio
/
Estrogênios Conjugados (USP)
/
Dieta Aterogênica
Limite:
Animals
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article