Abstract
The effect of orciprenaline on hypoxic pulmonary vasoconstriction and arterial oxygen tension (PaO2) was studied in 8 dogs by measuring the redistribution of blood flow in response to unilateral alveolar hypoxia. The distribution of blood flow was recorded continuously by measuring the radioactivity of the mixed expired gas from each lung during the continuous intravenous infusion of xenon-133. The hypoxic vasoconstrictor response was significantly depressed by an infusion of 1.0 micrograms/kg/min of orciprenaline but not by a dose of 0.1 micrograms/kg/min. PaO2 during unilateral hypoxia was significantly lower during the infusion of the high dose of orciprenaline than it was in the control periods before or after the infusion. A bolus dose of 0.5 mg significantly increased blood flow to a lung with established hypoxic vasoconstriction and also caused a significant reduction in PaO2. Since these effects were produced in the absence of airway pressure or pulmonary vascular pressure changes, it is concluded that orciprenaline may depress the hypoxic pulmonary vasoconstrictor response in dogs.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
