title: Characterization of the stimulus-response curve for hypoxic pulmonary vasoconstriction.
abstract: Lungs from seven healthy female, sea level rats were perfused and ventilated in vitro. Hypoxic pulmonary vasoconstriction was stimulated by changing the inspired gas from 21% oxygen to 6, 4, 3 or 0% oxygen (all gases contained 5% carbon dioxide and balance nitrogen). A sigmoid stimulus-response curve was derived by probit analysis with a 50% of maximum response (ED50) at an oxygen tension of 3.49 +/- 0.17 kPa. It is suggested that such characterizations of the response to hypoxia may allow a more precise comparison of the effects of species, age, sex and drugs on hypoxic pulmonary vasoconstriction.
mesh_terms: D000818:Animals; D005260:Female; D000860:Hypoxia / Q000503:physiopathology*; D066298:In Vitro Techniques; D011652:Pulmonary Circulation; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time / Q000502:physiology*; D014661:Vasoconstriction