title: Baroreflex activation in conscious rats modulates the joint inflammatory response via sympathetic function.
abstract: The baroreflex is a critical physiological mechanism controlling cardiovascular function by modulating both the sympathetic and parasympathetic activities. Here, we report that electrical activation of the baroreflex attenuates joint inflammation in experimental arthritis induced by the administration of zymosan into the femorotibial cavity. Baroreflex activation combined with lumbar sympathectomy, adrenalectomy, celiac subdiaphragmatic vagotomy or splenectomy dissected the mechanisms involved in the inflammatory modulation, highlighting the role played by sympathetic inhibition in the attenuation of joint inflammation. From the immunological standpoint, baroreflex activation attenuates neutrophil migration and the synovial levels of inflammatory cytokines including TNF, IL-1β and IL-6, but does not affect the levels of the anti-inflammatory cytokine IL-10. The anti-inflammatory effects of the baroreflex system are not mediated by IL-10, the vagus nerve, adrenal glands or the spleen, but by the inhibition of the sympathetic drive to the knee. These results reveal a novel physiological neuronal network controlling peripheral local inflammation.
authors.affiliation: Departments of Immunology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Gabriel S
authors.initials: GS
authors.lastname: Bassi
authors.affiliation: Departments of Physiology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Brognara
authors.affiliation: Departments of Physiology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Jaci A
authors.initials: JA
authors.lastname: Castania
authors.affiliation: Departments of Pharmacology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Jhimmy
authors.initials: J
authors.lastname: Talbot
authors.affiliation: Departments of Immunology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil; Departments of Pharmacology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Thiago M
authors.initials: TM
authors.lastname: Cunha
authors.affiliation: Departments of Immunology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil; Departments of Pharmacology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Fernando Q
authors.initials: FQ
authors.lastname: Cunha
authors.affiliation: Rutgers University - New Jersey Medical School, Newark, NJ 07103, USA.
authors.forename: Luis
authors.initials: L
authors.lastname: Ulloa
authors.affiliation: Departments of Pharmacology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Kanashiro
authors.affiliation: Departments of Physiology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Daniel P Martins
authors.initials: DP
authors.lastname: Dias
authors.affiliation: Departments of Physiology from the Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil. Electronic address: hcsalgado@fmrp.usp.br.
authors.forename: Helio C
authors.initials: HC
authors.lastname: Salgado
mesh_terms: D000315:Adrenalectomy; D000818:Animals; D001168:Arthritis / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology*; D017704:Baroreflex; D004195:Disease Models, Animal; D004558:Electric Stimulation; D007249:Inflammation / Q000378:metabolism / Q000503:physiopathology*; D018836:Inflammation Mediators / Q000378:metabolism; D007719:Knee Joint / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D009504:Neutrophils / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013156:Splenectomy; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D014628:Vagotomy; D015054:Zymosan
chemical_list: D018836:Inflammation Mediators; D015054:Zymosan
keywords: Baroreflex; Inflammation; Neuroimmunomodulation; Parasympathetic activity; Sympathetic activity