title: Involvement of the paraventricular nucleus (PVN) of hypothalamus in the cardiovascular alterations to head up tilt in conscious rats.
abstract: We evaluated the involvement of paraventricular nucleus (PVN) in the changes in mean arterial pressure (MAP) and heart rate (HR) during an orthostatic challenge (head up tilt, HUT). Adult male Wistar rats, instrumented with guide cannulas to PVN and artery and vein catheters were submitted to MAP and HR recording in conscious state and induction of HUT. The HUT induced an increase in MAP and HR and the pretreatment with prazosin and atenolol blocked these effects. After inhibition of neurotransmission with cobalt chloride (1 mM/100 nl) into the PVN the HR parameters did not change, however we observed a decrease in MAP during HUT. Our data suggest the involvement of PVN in the brain circuitry involved in cardiovascular adjustment during orthostatic challenges.
authors.affiliation: Department of Physiological Sciences, State University of Londrina, Londrina, PR, Brazil.
authors.forename: Ozahyr
authors.initials: O
authors.lastname: de Andrade
authors.forename: Marlusa Karlen
authors.initials: MK
authors.lastname: Amarante
authors.forename: Natália Veronez
authors.initials: NV
authors.lastname: da Cunha
authors.forename: Fernando Morgan
authors.initials: FM
authors.lastname: de Aguiar Corrêa
authors.forename: Marco Antonio Peliky
authors.initials: MA
authors.lastname: Fontes
authors.forename: Marli Cardoso
authors.initials: MC
authors.lastname: Martins-Pinge
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000494:pharmacology; D000818:Animals; D017704:Baroreflex / Q000187:drug effects / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D019416:Head Movements / Q000187:drug effects / Q000502:physiology*; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology*; D008297:Male; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000502:physiology*; D011224:Prazosin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D011224:Prazosin