title: Effect of conivaptan, a combined vasopressin V(1a) and V(2) receptor antagonist, on vasopressin-induced cardiac and haemodynamic changes in anaesthetised dogs.
abstract: The neurohormonal factor arginine vasopressin (AVP) produces potent systemic vasoconstriction as well as water retention in the kidneys via the V(1a) and V(2) receptors, respectively. Therefore, AVP may be considered as an aggravating factor of cardiac failure. In the present study, the effects of intravenous (i.v.) infusion of AVP on cardiovascular parameters and the effect of conivaptan (YM087, 4'-(2-methyl-1,4,5,6-tetrahydroimidazo[4,5-d][1]benzoazepine-6-carbonyl)-2-phenylbenzanilide monohydrochloride), a vasopressin V(1a)/V(2) receptor antagonist, on AVP-induced cardiac and haemodynamic changes were investigated in pentobarbitone-anaesthetised dogs. The i.v. infusion of AVP (0.12-4mUkg(-1)min(-1)) dose-dependently produced decreases in the cardiac contractility indicator LV dP/dt(max) and cardiac output (CO) and increases in left ventricular end-diastolic pressure (LVEDP) and total peripheral resistance (TPR). These changes accurately mimic the cardiovascular symptoms of congestive heart failure. The i.v. bolus injection of conivaptan (0.1mgkg(-1)) rapidly attenuated the AVP (4mUkg(-1)min(-1))-induced decrease in CO and reversed the AVP-induced elevation in both LVEDP and TPR. In conclusion, i.v. infusion of AVP produced cardiac dysfunction and vasoconstriction in pentobarbitone-anaesthetised dogs. Conivaptan demonstrated the ability to dramatically improve the impaired cardiovascular parameters induced by AVP. The results suggest the potential usefulness of conivaptan in treating congestive heart failure.
authors.affiliation: Pharmacology Laboratories, Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan. yatsu@yamanouchi.co.jp
authors.forename: Takeyuki
authors.initials: T
authors.lastname: Yatsu
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kusayama
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Tomura
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Arai
authors.forename: Motonori
authors.initials: M
authors.lastname: Aoki
authors.forename: Atsuo
authors.initials: A
authors.lastname: Tahara
authors.forename: Koh-Ichi
authors.initials: K
authors.lastname: Wada
authors.forename: Junko
authors.initials: J
authors.lastname: Tsukada
mesh_terms: D000758:Anesthesia; D000818:Animals; D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines / Q000494:pharmacology*; D002302:Cardiac Output / Q000187:drug effects; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D007262:Infusions, Intravenous; D008297:Male; D014667:Vasopressins / Q000008:administration & dosage*
chemical_list: D065092:Antidiuretic Hormone Receptor Antagonists; D001552:Benzazepines; C106389:conivaptan; D014667:Vasopressins