TY - JOUR
T1 - Cardiovascular responses to L-glutamate microinjection into the NTS are abrogated by reduced glutathione
AU - Granato, Álisson Silva
AU - Gomes, Paula Magalhães
AU - Martins Sá, Renato William
AU - Borges, Gabriel Silva Marques
AU - Alzamora, Andréia Carvalho
AU - de Oliveira, Lisandra Brandino
AU - Toney, Glenn M.
AU - Cardoso, Leonardo M.
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/3/6
Y1 - 2017/3/6
N2 - 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.
AB - 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.
KW - Blood pressure
KW - Glutathione
KW - L-glutamate
KW - Nucleus tractus solitaries
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U2 - 10.1016/j.neulet.2017.02.019
DO - 10.1016/j.neulet.2017.02.019
M3 - Article
C2 - 28189741
AN - SCOPUS:85012067048
SN - 0304-3940
VL - 642
SP - 142
EP - 147
JO - Neuroscience Letters
JF - Neuroscience Letters
ER -