Perivascular Adipose Tissue (PVAT) Prevents Hyporeactivity In The Aorta Of Mice With Acute Sepsis

Perivascular Adipose Tissue (PVAT) Prevents Hyporeactivity In The Aorta Of Mice With Acute Sepsis

• Autor
• Naiara Assis
• Co-autores
• Natália Nóbrega , Natália Araújo , Daniela Reis , Daniella Bonaventura
• Resumo

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  Introduction: Perivascular adipose tissue (PVAT) involves most of the blood vessels and releases biologically active molecules that regulate vascular tone. We hypothesize that PVAT is opposed to hyporeactivity caused by acute sepsis, by releasing vasoconstrictor substances, alleviating the vascular insufficiency that acute sepsis causes. Objective: To study the vasoactive and inflammatory effects of PVAT on aortic hyporeactivity induced by a systemic inflammatory process. Methods: Male Balb / c mice (8 weeks old) were divided into two groups: sham and septic. In the septic group, sepsis was induced by ligation and transverse perforation of the cecum with a 26G needle. In the sham group, the transverse perforation step of the cecum was not performed. 6 hours after sepsis induction, the role of PVAT in vascular tone was assessed in thoracic aortas of the sham and septic groups. (CEUA: 383/2016). Results: Although the sham and septic groups have 100% survival, the septic group presented leucopenia (neutropenia), hypothermia, arterial hypotension, high clinical score. Phenylephrine-induced vasoconstriction was significantly reduced in the septic group compared to the sham group in the absence of PVAT. However, when present, PVAT, reestablished contraction in the septic group. (sham PVAT - Emax: 2,81 ± 0,16 / pD2: 7,36 ± 0,12 n=4; septic PVAT - Emax: 2,13 ± 0,20 / pD2: 7,1 ± 0,14 n=4; septic PVAT + Emax: 3,00 ± 0,12 / pD2: 7,26 ± 0,09 n=10, respectively p>0,05). We suggest that the contractile profile presented by PVAT in acute sepsis is mainly due to the participation of superoxide anions, probably generated from the NADPH oxidase complex, but also vasocontractile derivatives of COX-2 and that both "feed" the cycle favoring the observed contraction. Conclusion: PVAT reversed the aortic hyporeactivity identified in acute sepsis through vasocontractile mediators, such as superoxide anion and COX vasoconstrictor derivatives: thromboxane A2 and prostaglandin F2?.

   

• Palavras-chave
• PVAT, Sepse, Reatividade vascular.
• Modalidade
• Pôster
• Área Temática
• Tecido adiposo perivascular