Modulation of the Contractile Response by the Thoracic Aorta Perivascular Adipose Tissue During Aging

Modulation of the Contractile Response by the Thoracic Aorta Perivascular Adipose Tissue During Aging

• Autor
• Abiqueila da Silva Alves
• Co-autores
• Bruno Vinícius Duarte Marques , Eliana Hiromi Akamine
• Resumo

• The perivascular adipose tissue (PVAT) surrounds most of blood vessels and has an anticontractile action, which is reduced in obesity and hypertension. Here, we evaluated the anticontractile action exerted by thoracic aorta PVAT of male mice with accelerated aging, SAMP-8, at 3 and 8 months of age, and whether the PVAT action depends on the release of diffusible factors or it is a mechanical influence. PVAT was removed (PVAT-) or kept intact (PVAT+) in aortic rings. In a set of experiments, PVAT- rings were incubated with its own PVAT (PVAT/exo) or PVAT- rings were incubated with PVAT from the animal of another age (PVAT/exc). Concentration-response curves for noradrenalin were performed. Data are shown as maximal response (mN/mm). CEUA/ICB: 82/2017. PVAT+ rings of 3-month SAMP-8 showed a higher response to noradrenaline in relation to PVATrings (PVAT-: 3.6±0.2, n=13; PVAT+: 5.1±0.1, n=11; P < 0.05), but when the PVAT of the animals was present but not directly attached to the ring, the increased response to noradrenaline was not observed. The response to noradrenaline was similar among PVAT-, PVAT+ and PVAT/exo rings of 8-month SAMP-8 (PVAT-: 3.7±0.2, n=7; PVAT+: 4.2±0.2, n=8; PVAT/exo: 3.9±0.2, n=8; P > 0.05). Comparing the response to noradrenaline between the ages, the response was similar in the PVAT- and PVAT/exo rings, but the response in PVAT+ rings of 8-month was smaller than that of 3-month SAMP-8 (P < 0.05). The response to noradrenaline was similar in PVAT/exc. The larger contractile response promoted by PVAT of the 3-month SAMP-8 suggests that PVAT dysfunction is already present at this age. In older animals, the reduced response may be related to loss of the contractile capacity of the artery, due to stiffness. Furthermore, our results show the necessity of the direct contact of PVAT with the artery to enable its action.

• Palavras-chave
• Aging, Thoracic aorta, Perivascular adipose tissue
• Modalidade
• Comunicação oral
• Área Temática
• Tecido adiposo perivascular