Vascular damage in obese female rats with hypoestrogenism
Increase in body weight and adiposity has deleterious consequences on health. The aim of this study was to compare morphological and metabolic changes in the arterial vessels of Wistar rats with conditions of obesity, hypoestrogenism, and hypoestrogenism plus obesity. Ovariectomized rats (hypoestrogenic condition) received 30 % sugar in drinking water plus standard diet during 10 weeks. The hypoestrogenic-obese (HE-OB) group presented increase in weight, blood pressure, hypertriglyceridemia, and hyperglycemia compared with other groups. The morphological study in aortic vessels from HE showed damage in endothelial smooth muscle tissue compared with the other groups. Adipose cells volume in HE-OB (59.33 ± 2.38 μ3 × 105) and obese (OB) (54.95 ± 1.36 μ3 × 105) groups were significantly larger than control group (36.38 ± 0.98 μ3 × 105). In the HE group adipocyte hyperplasia was observed, while in OB group adipocyte hypertrophy and hyperplasia was shown. The vascular reactivity in HE-OB and OB groups presented decrease in the relaxation to acetylcholine compared with control conditions (p < 0.05), whereas the addition of NG-nitro-l-arginine methyl ester resulted in a greater inhibition of relaxation in HE-OB and OB groups compared with control conditions (p < 0.05). These findings suggest that the dysfunction in blood vessels observed in estrogen deficiency and obesity conditions contributes to early cardiovascular alterations.