Central nitrergic system regulation of neuroendocrine secretion, fluid intake and blood pressure induced by angiotensin-II

Autor(es)

Reis, Wagner L. ^{[1, 2, 3]} ; Saad, Wilson A. ^[4] ; Camargo, Luiz A. ^[4] ; Elias, Lucila L. K. ^[4] ; Antunes-Rodrigues, Jose ^[1]

Afiliação do(s) autor(es)

^[1] Paulista State Univ Araraquara, UNESP, Sch Dent, Dept Physiol, Araraquara, SP - Brazil

^[2] Univ Taubate UNITAU, Basic Inst Biosci, Taubate, SP - Brazil

^[3] Centro Univ Araraquara, Dept Exact & Nat Sci, Araraquara, SP - Brazil

^[4] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Physiol, Neuroendocrinol Lab, BR-14049 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Behavioral and Brain Functions; v. 6, OCT 25 2010.
• Citações Web of Science: 19

Resumo

Background: Nitric oxide (NO) synthesis has been described in several circumventricular and hypothalamic structures in the central nervous system that are implicated in mediating central angiotensin-II (ANG-II) actions during water deprivation and hypovolemia. Neuroendocrine and cardiovascular responses, drinking behavior, and urinary excretions were examined following central angiotensinergic stimulation in awake freely-moving rats pretreated with intracerebroventricular injections of N omega-nitro-L-arginine methyl ester (L-NAME, 40 mu g), an inhibitor of NO synthase, and L-arginine (20 ug), a precursor of NO. Results: Injections of L-NAME or ANG-II produced an increase in plasma vasopressin (VP), oxytocin (OT) and atrial natriuretic peptide (ANP) levels, an increase in water and sodium intake, mean arterial blood pressure and sodium excretion, and a reduction of urinary volume. L-NAME pretreatment enhanced the ANG-II response, while L-arginine attenuated VP and OT release, thirst, appetite for sodium, antidiuresis, and natriuresis, as well as pressor responses induced by ANG-II. Discussion and conclusion: Thus, the central nitrergic system participates in the angiotensinergic responses evoked by water deprivation and hypovolemia to refrain neurohypophysial secretion, hydromineral balance, and blood pressure homeostasis. (AU)

• Processo FAPESP: 98/15846-0 - Controle neuroendócrino do equilíbrio hidroeletrolítico
• Beneficiário: José Antunes Rodrigues
• Modalidade de apoio: Auxílio à Pesquisa - Temático