title: The Responses of Pulmonary and Systemic Circulation and Airway to Allergic Mediators in Anesthetized Rats.
abstract: Lung allergic diseases sometimes accompany pulmonary vaso- and broncho-constriction. Rats are currently used for the experimental study of lung allergies. However, their hemodynamic mechanisms are not fully understood. Therefore the effects of allergic mediators were determined systematically in vivo in rats in terms of pulmonary vascular resistance (PVR), airway pressure (AWP) and total peripheral resistance (TPR). We directly measured pulmonary arterial pressure, left atrial pressure, systemic arterial pressure, central venous pressure and aortic blood flow to determine PVR and TPR, as well as AWP, following injections of platelet-activating factor (PAF), histamine, serotonin, leukotriene (LT) C4, and prostaglandin (PG) D2 in anesthetized open-chest artificially ventilated Sprague-Dawley (SD) rats. PVR was dose-dependently increased by consecutive administration of PAF, LTC4, and PGD2, with the maximal responsiveness being PAF>LTC4>PGD2. However, neither histamine nor serotonin changed PVR. TPR was decreased by all agents except LTC4 which actually increased it. PAF and serotonin, but not the other agents, increased AWP. In conclusion, allergic mediators exert non-uniform actions on pulmonary and systemic circulation and airways in anesthetized SD rats: PAF, LTC4 and PGD2, but not histamine or serotonin, caused substantial pulmonary vasoconstriction; LTC4 yielded systemic vasoconstriction, while the others caused systemic vasodilatation; only two mediators, PAF and serotonin, induce airway constriction.
authors.affiliation: Department of Physiology II, Kanazawa Medical University.
authors.forename: Mofei
authors.initials: M
authors.lastname: Wang
authors.forename: Toshishige
authors.initials: T
authors.lastname: Shibamoto
authors.forename: Yuhichi
authors.initials: Y
authors.lastname: Kuda
authors.forename: Mamoru
authors.initials: M
authors.lastname: Tanida
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Song
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Mukai
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Kurata
mesh_terms: D000758:Anesthesia; D000818:Animals; D062186:Arterial Pressure / Q000187:drug effects; D001775:Blood Circulation / Q000187:drug effects*; D006632:Histamine / Q000494:pharmacology; D006967:Hypersensitivity / Q000503:physiopathology; D018836:Inflammation Mediators / Q000494:pharmacology*; D017997:Leukotriene C4 / Q000494:pharmacology; D008168:Lung / Q000187:drug effects* / Q000502:physiology; D008297:Male; D010972:Platelet Activating Factor / Q000494:pharmacology; D015230:Prostaglandin D2 / Q000494:pharmacology; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000494:pharmacology; D014655:Vascular Resistance / Q000187:drug effects*; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D018836:Inflammation Mediators; D010972:Platelet Activating Factor; D017997:Leukotriene C4; D012701:Serotonin; D006632:Histamine; D015230:Prostaglandin D2