Influência do Gênero Sobre a Regurgitação Aórtica, Deposição Lipídica e Senescência Vascular em Camundongos Idosos Ateroscleróticos

• Ano de defesa: 2009
• Autor(a) principal: Pereira, Thiago de Melo Costa
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Doutorado em Ciências Fisiológicas; Centro de Ciências da Saúde; UFES; Programa de Pós-Graduação em Ciências Fisiológicas
• Palavras-chave em Português: Fisiologia; 612
• Link de acesso: http://repositorio.ufes.br/handle/10/5166

Although exhausting evidences have investigated age-related differences in cardiovascular performance, the impact of gender on such age-associated cardiovascular changes can be more explained. Such investigations would be important because the gender-related differences in cardiovascular aging may help to explain in part the greater longevity of women and of females of most of the mammalian species. Our aim was to investigate in aged mice morphophysiological alterations related to gender and dyslipidemia through the angiography, histological and enzymatic assays. We studied senescent mice of 18 months of age, separate in the groups: C57 (female: n=26; males: n=22; ovariectomized: n=10) and ApoE (female: n=28 and males: n=23; ovariectomized: n=7). After carotid catheterization, was realized the angiography for analysis of internal diameter (ID), aortic regurgitation (AR) and other parameters. Immediately after, the animals were submitted the histological or biochemical assays for detection of areas of lipid deposition (LD), vascular senescence (VS) and cholesterlemia. Statistical analysis was performed with Student's t or 1-way ANOVA followed by the Tukey post hoc test (*p<0,05). The angiography did not show significant differences between C57 and ApoE mice in relation to ID and aortic blood flow velocity (95,4 ± 6,2 vs 102 ± 5,7 mm/s, respectively). After the histological analysis, was confirmed the increase of external diameter in ApoE animals (2617 ± 149 mm2 ) when compared with C57 (1396 ± 159 mm2 , p<0,001). In the histochemical evaluation of aorta, only the male ApoE animals showed a significantly severity of LD (C57 female: 0.11 ± 0,01; C57 male: 0.12 ± 0,01; ApoE female: 0.21 ± 0,04 and ApoE male: 0.35 ± 0.05* cm2 ) and VS (0.01 ± 0.008, 0.016 ± 0.01, 0.025 ± 0.02 e 0.19 ± 0.08* cm2 , respectively)having a correlation with cholesterolemia of the C57 groups (female: 81 ± 4 vs. male: 96 ± 6 mg/dL) and ApoE groups (female: 336 ± 32* vs. male: 650 ± 92* mg/dL). It was a remarkable level of severity of AR in male compared with female both in C57 (female: 0.7 ± 0.24 vs. male: 3 ± 0.24*) and ApoE (female: 0.8 ± 0.2 vs.male: 2.3 ± 0.3*). We found a good correlation between valvular regurgitation and histologically assessed valvular thickness, without pathological or compensatory mechanisms. After 12 months, the C57 and ApoE ovariectomized females did not show difference in LD, VS, cholesterolemia or AR between respective female groups. Therefore, our data suggest an important participation of gender-related differences in cardiovascular aging, showing that endogenous/genetics factors can be essentials for development of cardiovascular diseases.