title: Vascular tracers alter hemodynamics and airway pressure in anesthetized sheep.
abstract: The technique of vascular labeling was developed to mark sites of increased microvascular permeability. We used the vascular labeling technique in anesthetized sheep and found that hemodynamics and airway pressure were adversely affected by intraarterial infusions of two vascular tracers. Monastral blue (nine sheep) immediately caused systemic arterial hypotension, pulmonary arterial hypertension, and bronchoconstriction. All three physiological responses were partially blocked by a cyclooxygenase inhibitor (indomethacin) but not by an H1-antihistamine (chlorpheniramine). Colloidal gold (nine sheep) caused immediate, but less dramatic, pulmonary arterial hypertension which was not attenuated by the blocking agents. We conclude that these two vascular tracers caused detrimental physiological side effects in sheep at the usual doses used to label injured microvessels in other species.
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002199:Capillary Permeability; D002744:Chlorpheniramine / Q000494:pharmacology; D006048:Gold Colloid, Radioactive; D006439:Hemodynamics / Q000187:drug effects*; D007211:Indoles; D007213:Indomethacin / Q000494:pharmacology; D008168:Lung / Q000648:ultrastructure; D008854:Microscopy, Electron; D009942:Organometallic Compounds; D011312:Pressure; D012123:Pulmonary Ventilation / Q000187:drug effects*; D012756:Sheep
chemical_list: D006048:Gold Colloid, Radioactive; D007211:Indoles; D009942:Organometallic Compounds; D002744:Chlorpheniramine; C015445:copper phthalocyanine; D007213:Indomethacin