title: Importance of the central nucleus of the amygdala on sodium intake caused by deactivation of lateral parabrachial nucleus.
abstract: The lateral parabrachial nucleus (LPBN) and the central nucleus of the amygdala (CeA) are important central areas for the control of sodium appetite. In the present study, we investigated the importance of the facilitatory mechanisms of the CeA on NaCl and water intake produced by the deactivation of LPBN inhibitory mechanisms. Male Holtzman rats (n=7-14) with stainless steel cannulas implanted bilaterally in the CeA and LPBN were used. Bilateral injections of moxonidine (α2-adrenoceptor/imidazoline agonist, 0.5 nmol/0.2 μl) into the LPBN increased furosemide+captopril-induced 0.3M NaCl (29.7 ± 7.2, vs. vehicle: 4.4 ± 1.6 ml/2h) and water intake (26.4 ± 6.7, vs. vehicle: 8.2 ± 1.6 ml/2h). The GABAA agonist muscimol (0.25 nmol/0.2 μl) injected bilaterally into the CeA abolished the effects of moxonidine into the LPBN on 0.3M NaCl (2.8 ± 1.6 ml/2h) and water intake (3.3 ± 2.3 ml/2h). Euhydrated rats treated with muscimol (0.5 nmol/0.2 μl) into the LPBN also ingested 0.3M NaCl (19.1 ± 6.4 ml/4h) and water (8.8 ± 3.2 ml/4h). Muscimol (0.5 nmol/0.2 μl) into the CeA also abolished 0.3M NaCl (0.1 ± 0.04 ml/4h) and water intake (0.1 ± 0.02 ml/4h) in euhydrated treated with muscimol into the LPBN. The present results show that neuronal deactivation of the CeA abolishes NaCl intake produced by the blockade of LPBN inhibitory mechanisms, suggesting an interaction between facilitatory mechanisms of the CeA and inhibitory mechanisms of the LPBN in the control of NaCl intake.
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Gláucia M F
authors.initials: GM
authors.lastname: Andrade-Franzé
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Carina A F
authors.initials: CA
authors.lastname: Andrade
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Silvia
authors.initials: S
authors.lastname: Gasparini
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Laurival A
authors.initials: LA
authors.lastname: De Luca
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Patrícia M
authors.initials: PM
authors.lastname: De Paula
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Débora S A
authors.initials: DS
authors.lastname: Colombari
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Colombari
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University (UNESP), Araraquara, SP 14801-903, Brazil. Electronic address: menani@foar.unesp.br.
authors.forename: José V
authors.initials: JV
authors.lastname: Menani
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D002216:Captopril / Q000494:pharmacology; D066274:Central Amygdaloid Nucleus / Q000187:drug effects / Q000502:physiology*; D004326:Drinking / Q000187:drug effects; D004327:Drinking Behavior / Q000187:drug effects*; D005665:Furosemide / Q000494:pharmacology; D058785:GABA-A Receptor Agonists / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D008297:Male; D009118:Muscimol / Q000494:pharmacology; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D065823:Parabrachial Nucleus / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012964:Sodium / Q000378:metabolism*; D049994:Sodium Potassium Chloride Symporter Inhibitors / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000959:Antihypertensive Agents; D058785:GABA-A Receptor Agonists; D007093:Imidazoles; D049994:Sodium Potassium Chloride Symporter Inhibitors; D009118:Muscimol; D005665:Furosemide; D002216:Captopril; D012964:Sodium; C043482:moxonidine
keywords: Amygdala; Angiotensin II; GABA; Parabrachial nucleus; Sodium appetite; Thirst