Effect of Chronic Ethanol Consumption on the Modulatory Action Displayed by Perivascular Adipose Tissue: Participation of Angiotensin II

Effect of Chronic Ethanol Consumption on the Modulatory Action Displayed by Perivascular Adipose Tissue: Participation of Angiotensin II

• Autor
• Wanessa Mayumi Carvalho Awata
• Co-autores
• Arthur Henrique de Sousa , Carlos Renato Tirapelli
• Resumo

• Introduction: Renin-angiotensin system plays a role in ethanol-induced hypertension and vascular dysfunction. Perivascular adipose tissue (PVAT) is recognized as a regulatory element in vascular biology that is implicated in the pathophysiology of cardiovascular diseases. Hypertension-induced vascular inflammation is initiated in PVAT and angiotesnin II (ANGII) is an important mediator of this response. However, there are no studies describing the impact of chronic ethanol consumption on the modulatory action exerted by PVAT on vascular tone.Since PVAT plays an important role in regulating vascular function, the present study was designed to investigate the consequences of ethanol consumption on the modulatory action that PVAT exerts on vascular tone. Methods: Male Wistar Hannover rats (260-280 g) were randomized in 4 groups: 1) Control; 2) Ethanol (20%, vol./vol.); 3) Losartan (10 mg/kg/day; p.o. gavage); 4) Ethanol (20%, vol./vol.) + Losartan (10 mg/kg/day; p.o. gavage). Concentration-response curves for phenylephrine were obtained in thoracic aorta with or without PVAT [PVAT (+) and PVAT(-), respectively) with [Endo(+)] and without endothelium [(Endo (-)] after one week of treatment. [CEUA 19.1.937.22.3] Results: Ethanol consumption increased the contraction (in mN) induced by phenylephrine – that is, impaired the anti-contractile effect of PVAT when compared to contraction of control group [PVAT(+): Endo(-): Control: 10.6 ± 0.2 mN n=5; Ethanol: 17.9 ± 2.1mN* n=8; Endo(+): Control: 8.1 ± 0.2mN n=7; Ethanol: 13.1 ±1.0mN* n=14). Treatment with losartan attenuated this response [PVAT(+): Endo(-):10.3 ± 0.5mN n=9; Endo(+): 9.2 ± 0.5mN n=7].The loss of the anti-contractile effect of PVAT was reversed after incubating the arteries with tiron or indomethacin. Conclusion: Chronic ethanol consumption induced loss of the anticontractile effect of PVAT and treatment with losartan prevented this response. Functional experiments showed a role for reactive oxygen species (ROS) and cyclooxygenase (COX)-derived metabolites in such response.These responses were accompanied by impairment of NO bioavailability. 

• Palavras-chave
• PVAT, Ethanol, Angiotensin ll, EROs
• Modalidade
• Pôster
• Área Temática
• Tecido adiposo perivascular