title: The anteroventral third ventricle (AV3V) region is essential for pressor, dipsogenic and natriuretic responses to central carbachol.
abstract: In the present study we investigated the effect of anteroventral third ventricle (AV3V) lesion on pressor, dipsogenic and natriuretic responses produced by the intracerebroventricular (i.c.v.) injection of a cholinergic agonist (carbachol). Freely moving rats with AV3V or sham lesion (1-2 days and 9-12 days) and a delay cannula implanted into the lateral ventricle were studied. Changes in mean arterial pressure (MAP, 1 h record), water intake (1 h) and Na+ excretion (2 h) were analysed after i.c.v. injection of carbachol (7.5 nmol). In sham rats, i.c.v. injection of carbachol produced an increase in MAP (35 +/- 2 mmHg), water ingestion (7.7 +/- 1.2 ml/h) and Na+ excretion (626 +/- 42 microEq/120 min). The effects of i.c.v. carbachol injection were reduced 1-2 days after AV3V lesion (delta MAP = 6 +/- 2 mmHg, water ingestion = 0.3 +/- 0.3 ml/h and Na+ excretion = 31 +/- 11 microEq/120 min) and 9-12 days (delta MAP = 11 +/- 3 mmHg, water ingestion = 3.3 +/- 0.9 ml/h and Na+ excretion = 37 +/- 11 microEq/120 min). These results show that the AV3V region is essential for the full development of the pressor, dipsogenic and natriuretic responses produced by central cholinergic receptors.
authors.affiliation: Department of Physiology, School of Dentistry, Paulista State University, Araraquara, Brazil.
authors.forename: J V
authors.initials: JV
authors.lastname: Menani
authors.forename: W A
authors.initials: WA
authors.lastname: Saad
authors.forename: L A
authors.initials: LA
authors.lastname: Camargo
authors.forename: A
authors.initials: A
authors.lastname: Renzi
authors.forename: L A
authors.initials: LA
authors.lastname: De Luca Júnior
authors.forename: E
authors.initials: E
authors.lastname: Colombari
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D002217:Carbachol / Q000494:pharmacology*; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D002799:Cholinergic Fibers / Q000187:drug effects / Q000502:physiology*; D004327:Drinking Behavior / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D014554:Urination / Q000187:drug effects*
chemical_list: D002217:Carbachol