title: Median preoptic nucleus mediates the cardiovascular recovery induced by hypertonic saline in hemorrhagic shock.
abstract: Changes in plasma osmolarity, through central and peripheral osmoreceptors, activate the median preoptic nucleus (MnPO) that modulates autonomic and neuroendocrine adjustments. The present study sought to determine the participation of MnPO in the cardiovascular recovery induced by hypertonic saline infusion (HSI) in rats submitted to hemorrhagic shock. The recordings of mean arterial pressure (MAP) and renal vascular conductance (RVC) were carried out on male Wistar rats (250-300 g). Hemorrhagic shock was induced by blood withdrawal over 20 min until the MAP values of approximately 60 mmHg were attained. The nanoinjection (100 nL) of GABAA agonist (Muscimol 4 mM; experimental group (EXP)) or isotonic saline (NaCl 150 mM; control (CONT)) into MnPO was performed 2 min prior to intravenous overload of sodium through HSI (3 M NaCl, 1.8 mL/kg, b.wt.). Hemorrhagic shock reduced the MAP in control (62 ± 1.1 mmHg) and EXP (61 ± 0.4 mmHg) equipotently. The inhibition of MnPO impaired MAP (CONT: 104 ± 4.2 versus EXP: 60 ± 6.2 mmHg) and RVC (CONT: 6.4 ± 11.4 versus EXP: -53.5 ± 10.0) recovery 10 min after HSI. The overall results in this study demonstrated, for the first time, that the MnPO plays an essential role in the HSI induced resuscitation during hypovolemic hemorrhagic shock.
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: Nathalia Oda
authors.initials: NO
authors.lastname: Amaral
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: Lara Marques
authors.initials: LM
authors.lastname: Naves
authors.affiliation: Faculty of Physical Education, Federal University of Uberlândia, Rua Bejamin Constant 1286, 14801-903 Uberlândia, MG, Brazil.
authors.forename: Marcos Luiz
authors.initials: ML
authors.lastname: Ferreira-Neto
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: André Henrique
authors.initials: AH
authors.lastname: Freiria-Oliveira
authors.affiliation: Department of Physiology and Pathology, São Paulo State University (UNESP), Rua Humaita 1680, 14801-903 Araraquara, SP, Brazil.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Colombari
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: Daniel Alves
authors.identifier: 0000-0002-7036-0840
authors.initials: DA
authors.lastname: Rosa
authors.affiliation: Department of Biochemistry and Molecular Biology, Biological Sciences Institute, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: Angela Adamski da Silva
authors.initials: AA
authors.lastname: Reis
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: Danielle
authors.identifier: 0000-0001-5709-9329
authors.initials: D
authors.lastname: Ianzer
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil.
authors.forename: Carlos Henrique
authors.initials: CH
authors.lastname: Xavier
authors.affiliation: Center for Neuroscience and Cardiovascular Physiology, Federal University of Goiás, Estrada do Campus s/n, 74690-900 Goiânia, GO, Brazil ; Department of Physiological Science, Universidade Federal de Goiás, Estrada do Campus s/n, P.O. Box 131, 74001-970 Goiânia, GO, Brazil.
authors.forename: Gustavo Rodrigues
authors.initials: GR
authors.lastname: Pedrino
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D006400:Hematocrit; D020896:Hypovolemia / Q000503:physiopathology; D008297:Male; D009994:Osmolar Concentration; D011301:Preoptic Area / Q000187:drug effects / Q000503:physiopathology*; D017208:Rats, Wistar; D020127:Recovery of Function / Q000187:drug effects*; D012462:Saline Solution, Hypertonic / Q000494:pharmacology* / Q000627:therapeutic use*; D012771:Shock, Hemorrhagic / Q000188:drug therapy* / Q000503:physiopathology*; D012964:Sodium / Q000097:blood
chemical_list: D012462:Saline Solution, Hypertonic; D012964:Sodium