Effects of histamine, serotonin, and norepinephrine on circulation of dog lungs.
The action of histamine (H), serotonin (5-HT), and norepinephrine (NE) on the lung vasculature was evaluated in isolated blood-perfused dog lung lobes using isogravimetric techniques. Pre- and postcapillary resistances, isogravimetric capillary pressure (Pc,i), capillary filtration pressure (Pc,f), capillary filtration coefficient (Kf,c), and vascular pressure-volume relationships were measured. For constant-flow conditions, all drugs induced marked increases in both pre- and postcapillary resistances and increased Pc,f. The rise in Pc,f was most pronounced for H and least marked for NE and 5-HT. For constant-pressure perfusion, Pc,f increased slightly for H but not for NE and 5-HT, while total vascular resistance increased 4-5 times for all drugs. Vascular distensibility and volumes decreased markedly for NE and 5-HT but only slightly for H. None of the drugs appeared to alter capillary permeability because Kf,c and Pc,i measured during the infusions were not different from control.
D000818:Animals; D001794:Blood Pressure; D001810:Blood Volume; D002199:Capillary Permeability; D004285:Dogs; D006439:Hemodynamics; D006632:Histamine / Q000494:pharmacology*; D008168:Lung / Q000098:blood supply / Q000502:physiology; D008833:Microcirculation; D009638:Norepinephrine / Q000494:pharmacology*; D011652:Pulmonary Circulation / Q000187:drug effects*; D012701:Serotonin / Q000494:pharmacology*; D014655:Vascular Resistance / Q000187:drug effects; D014690:Venous Pressure
D012701:Serotonin; D006632:Histamine; D009638:Norepinephrine