title: Role of adrenergic pathways of the medial preoptic area in ANGII-induced water intake and renal excretion in rats.
abstract: In this study, we investigated the participation of adrenergic neurotransmission in angiotensin II- (ANGII)-induced water intake and urinary electrolyte excretion by means of injection of the alpha 1-, alpha 2-, and beta-adrenoceptor antagonists and ANGII into the medial preoptic area (MPOA) in rats. Prazosin (an alpha 1-adrenergic antagonist) antagonized the water ingestion, Na+, K+ and urine excretion induced by ANGII, whereas yohimbine (an alpha 2-adrenergic antagonist) enhanced the Na+, K+ and urine excretion induced by ANGII. Propranolol (a nonselective beta-adrenoceptor blocker) antagonized the water ingestion and enhanced the Na+, and urine excretion induced by ANGII. Previous treatment with prazosin reduced the pressor responses to ANGII, whereas yohimbine had opposite effects. Previous injection of propranolol produced no effects in the pressor responses to ANGII. These results suggest that the adrenergic neurotransmission in the MPOA may actively participate in ANGII-induced dipsogenesis, natriuresis, kaliuresis and diuresis in a process that involves alpha 1-, alpha 2-, and beta-adrenoceptors.
authors.affiliation: Department of Physiology, Dentistry School, Paulista State University (UNESP), Araraquara, Brazil.
authors.forename: R
authors.initials: R
authors.lastname: Bastos
authors.forename: W A
authors.initials: WA
authors.lastname: Saad
authors.forename: J V
authors.initials: JV
authors.lastname: Menani
authors.forename: A
authors.initials: A
authors.lastname: Renzi
authors.forename: J E
authors.initials: JE
authors.lastname: Silveira
authors.forename: L A
authors.initials: LA
authors.lastname: Camargo
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists; D058669:Adrenergic alpha-2 Receptor Antagonists; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D017776:Autonomic Pathways / Q000033:anatomy & histology / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects; D004326:Drinking / Q000187:drug effects*; D007267:Injections; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009318:Natriuresis / Q000187:drug effects; D011188:Potassium / Q000652:urine; D011224:Prazosin / Q000008:administration & dosage / Q000494:pharmacology; D011301:Preoptic Area / Q000033:anatomy & histology / Q000502:physiology*; D011433:Propranolol / Q000008:administration & dosage / Q000494:pharmacology; D051381:Rats; D015016:Yohimbine / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D058669:Adrenergic alpha-2 Receptor Antagonists; D000319:Adrenergic beta-Antagonists; D000804:Angiotensin II; D015016:Yohimbine; D011433:Propranolol; D011188:Potassium; D011224:Prazosin