title: Endogenous angiotensin II in the NTS contributes to sympathetic activation in rats with aortocaval shunt.
abstract: Recent studies have suggested that the central nervous system is responsible for activation of sympathetic nerve activity (SNA) and the renin-angiotensin system in heart failure (HF). The aim of this study was to determine whether activation of the renin-angiotensin system within the nucleus of the solitary tract (NTS) plays a role in enhanced SNA in HF. High-output HF was induced by an aortocaval (A-V) shunt with some modifications in the rat. These rats exhibited a left ventricular dilatation and hemodynamic signs of high-output HF. Urinary catecholamine excretion and maximal renal SNA (RSNA) were greater in the A-V shunted rats than in the control rats. Microinjection of an angiotensin II type 1-receptor antagonist, CV11974, into the NTS was performed. The arterial pressure and RSNA were reduced by CV11974 to a greater degree in the A-V shunted rats than in the control rats. The expression of angiotensin-converting enzyme mRNA in the medulla was greater in the A-V shunted rats than in the control rats. These results suggest that activation of the renin-angiotensin system within the NTS contributes to an enhanced SNA in this model.
authors.affiliation: Department of Cardiovascular Medicine, Cardiovascular Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shigematsu
authors.forename: Y
authors.initials: Y
authors.lastname: Hirooka
authors.forename: K
authors.initials: K
authors.lastname: Eshima
authors.forename: M
authors.initials: M
authors.lastname: Shihara
authors.forename: T
authors.initials: T
authors.lastname: Tagawa
authors.forename: A
authors.initials: A
authors.lastname: Takeshita
mesh_terms: D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D001011:Aorta / Q000601:surgery*; D001166:Arteriovenous Shunt, Surgical; D001562:Benzimidazoles / Q000494:pharmacology; D001713:Biphenyl Compounds; D001794:Blood Pressure / Q000187:drug effects; D004452:Echocardiography; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics; D007093:Imidazoles / Q000494:pharmacology; D007668:Kidney / Q000294:innervation; D008297:Male; D008845:Microinjections; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D011921:Rats, Inbred WKY; D017552:Solitary Nucleus / Q000187:drug effects / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D013777:Tetrazoles / Q000494:pharmacology; D014684:Venae Cavae / Q000601:surgery*
chemical_list: D000959:Antihypertensive Agents; D001562:Benzimidazoles; D001713:Biphenyl Compounds; D007093:Imidazoles; D011725:Pyridines; D013777:Tetrazoles; D000804:Angiotensin II; C073402:PD 123319; C081643:candesartan