Importance of the commissural nucleus of the solitary tract in renovascular hypertension

Autor(es)

Melo, Mariana Rosso ^[1] ; Gasparini, Silvia ^[1] ; Speretta, Guilherme F. ^[1] ; Silva, Elaine Fernanda ^[2] ; Pedrino, Gustavo Rodrigues ^[2] ; Menani, V, Jose ; Zoccal, Daniel B. ^[3] ; Almeida Colombari, Debora Simoes ^[3] ; Colombari, Eduardo ^[3]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ, Dept Physiol & Pathol, UNESP, Sch Dent, Araraquara, SP - Brazil

^[2] Univ Fed Goias, Ctr Neurosci & Cardiovasc Res, Dept Physiol Sci, Biol Sci Inst, Goiania, Go - Brazil

^[3] Menani, Jose, V, Sao Paulo State Univ, Dept Physiol & Pathol, UNESP, Sch Dent, Araraquara, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: HYPERTENSION RESEARCH; v. 42, n. 5, p. 587-597, MAY 2019.
• Citações Web of Science: 1

Resumo

The rodent renovascular hypertension model has been used to investigate the mechanisms promoting hypertension. The importance of the carotid body for renovascular hypertension has been demonstrated. As the commissural NTS (cNTS) is the first synaptic site in the central nervous system that receives information from carotid body chemoreceptors, we evaluated the contribution of cNTS to renovascular hypertension in the present study. Normotensive male Holtzman rats were implanted with a silver clip around the left renal artery to induce two-kidney, one-clip (2K1C) hypertension. Six weeks later, isoguvacine (a GABA(A) agonist) or losartan (an AT1 antagonist) was injected into the cNTS, and the effects were compared with carotid body removal. Immunohistochemistry for Iba-1 and GFAP to label microglia and astrocytes, respectively, and RT-PCR for components of the renin-angiotensin system and cytokines in the NTS were also performed 6 weeks after renal surgery. The inhibition of cNTS with isoguvacine or the blockade of AT1 receptors with losartan in the cNTS decreased the blood pressure and heart rate of 2K1C rats even more than carotid body removal did. The mRNA expression of NOX2, TNF-alpha and IL-6, microglia, and astrocytes also increased in the cNTS of 2K1C rats compared to that of normotensive rats. These results indicate that tonically active neurons within the cNTS are essential for the maintenance of hypertension in 2K1C rats. In addition to signals from the carotid body, the present results suggest that angiotensin II directly activates the cNTS and may also induce microgliosis and astrogliosis within the NTS, which, in turn, cause oxidative stress and neuroinflammation. (AU)

• Processo FAPESP: 14/01159-6 - Papel das espécies reativas de oxigênio (EROs) no NTS sobre o desenvolvimento e a manutenção da hipertensão renovascular 2 rins 1 clipe
• Beneficiário: Mariana Del Rosso de Melo
• Linha de fomento: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/17251-6 - Mecanismos neurais de geração do padrão respiratório e do acoplamento simpático-respiratório em condições de hipóxia
• Beneficiário: Daniel Breseghello Zoccal
• Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores
• Processo FAPESP: 15/23467-7 - Fisiopatologia experimental: mecanismos centrais de controle cardiovascular e respiratório envolvidos em modelos experimentais de hipertensão e obesidade
• Beneficiário: Eduardo Colombari
• Linha de fomento: Auxílio à Pesquisa - Temático