title: Cardiovascular responses to l-glutamate microinjection into the NTS are abrogated by reduced glutathione.
abstract: Redox imbalance in regions of the CNS controlling blood pressure is increasingly recognized as a leading factor for hypertension. Nucleus tractus solitarius (NTS) of the dorsomedial medulla is the main region receiving excitatory visceral sensory inputs that modulate autonomic efferent drive to the cardiovascular system. This study sought to determine the capacity of reduced glutathione, a major bioactive antioxidant, to modulate NTS-mediated control of cardiovascular function in unanaesthetized rats. Male Fischer 344 rats were used for microinjection experiments. Cardiovascular responses to l-glutamate were first used to verify accurate placement of injections into the dorsomedial region comprising the NTS. Next, responses to GSH or vehicle were recorded followed by responses to l-glutamate again at the same site. GSH microinjection increased mean arterial pressure (MAP) compared to vehicle and abrogated responses to subsequent injection of l-glutamate. These data indicate that GSH microinjection into the NTS affects blood pressure regulation by dorsomedial neuronal circuits and blunts l-glutamate driven excitation in this region. These findings raise the possibility that increased antioxidant actions of GSH in NTS could contribute to autonomic control dysfunctions of the cardiovascular system.
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
authors.forename: Álisson Silva
authors.initials: ÁS
authors.lastname: Granato
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
authors.forename: Paula Magalhães
authors.initials: PM
authors.lastname: Gomes
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
authors.forename: Renato William
authors.initials: RW
authors.lastname: Martins Sá
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
authors.forename: Gabriel Silva Marques
authors.initials: GS
authors.lastname: Borges
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
authors.forename: Andréia Carvalho
authors.initials: AC
authors.lastname: Alzamora
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil.
authors.forename: Lisandra Brandino
authors.initials: LB
authors.lastname: de Oliveira
authors.affiliation: Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Toney
authors.affiliation: Federal University of Ouro Preto, Department of Biological Sciences/NUPEB, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG, 35,400-000 Brazil. Electronic address: leomcardoso@gmail.com.
authors.forename: Leonardo M
authors.initials: LM
authors.lastname: Cardoso
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D018698:Glutamic Acid / Q000494:pharmacology*; D005978:Glutathione / Q000494:pharmacology*; D008297:Male; D008845:Microinjections; D009474:Neurons / Q000187:drug effects; D051381:Rats; D011916:Rats, Inbred F344; D017552:Solitary Nucleus / Q000187:drug effects*
chemical_list: D018698:Glutamic Acid; D005978:Glutathione
keywords: Blood pressure; Glutathione; L-glutamate; Nucleus tractus solitaries