title: Involvement of non-NMDA glutamate receptors of the hypothalamic paraventricular nucleus in the cardiovascular response to the microinjection of noradrenaline into the dorsal periaqueductal gray area of rats.
abstract: The dorsal periaqueductal gray area (dPAG) is involved in cardiovascular modulation. In a previous study, we showed that noradrenaline (NA) microinjected into the dPAG caused a vasopressin-mediated pressor response, involving a relay in the hypothalamic paraventricular nucleus (PVN). In the present study, we evaluated the involvement of ionotropic glutamate receptors within the PVN in the cardiovascular response to NA microinjection into the dPAG of unanesthetized rats. Microinjection of the selective NMDA glutamate receptor antagonist LY235959 (2nmol/100nL) unilaterally into the PVN did not affect the cardiovascular response evoked by microinjection of NA (15nmol/50nL) into the dPAG. On the other hand, unilateral PVN pretreatment with the non-NMDA glutamate receptor antagonist NBQX (2nmol/100nL) significantly reduced the pressor and cardiac response caused by microinjection of NA into the dPAG. In addition, bilateral PVN pretreatment with NBQX (2nmol/100nL) blocked the cardiovascular response to NA injected into the dPAG. In conclusion, the present results suggest that bilateral PVN activation of non-NMDA glutamate receptors mediates the vasopressin-related cardiovascular response to the microinjection of NA into the dPAG.
authors.affiliation: Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, 14040-900 São Paulo, Brazil; Department of Physiological Sciences, Center of Biological Sciences, State University of Londrina, Londrina, PR, Brazil. Electronic address: pelosigg@gmail.com.
authors.forename: Gislaine Garcia
authors.initials: GG
authors.lastname: Pelosi
authors.affiliation: Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, 14040-900 São Paulo, Brazil.
authors.forename: Cristiane
authors.initials: C
authors.lastname: Busnardo
authors.affiliation: Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, 14040-900 São Paulo, Brazil.
authors.forename: Rodrigo Fiacadori
authors.initials: RF
authors.lastname: Tavares
authors.affiliation: Department of Pharmacology, School of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, 14040-900 São Paulo, Brazil.
authors.forename: Fernando Morgan Aguiar
authors.initials: FM
authors.lastname: Corrêa
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D001919:Bradycardia / Q000378:metabolism; D002408:Catheters, Indwelling; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology*; D007546:Isoquinolines / Q000494:pharmacology; D008297:Male; D008845:Microinjections; D009638:Norepinephrine / Q000008:administration & dosage / Q000378:metabolism*; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000378:metabolism*; D010487:Periaqueductal Gray / Q000187:drug effects / Q000378:metabolism*; D011810:Quinoxalines / Q000494:pharmacology; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000316:Adrenergic alpha-Agonists; D018691:Excitatory Amino Acid Antagonists; D007546:Isoquinolines; D011810:Quinoxalines; D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline; C088643:LY 235959; D009638:Norepinephrine
keywords: Blood pressure; Non-NMDA glutamate receptors; Noradrenaline; Paraventricular nucleus of hypothalamus; Periaqueductal gray area; Vasopressin