Fig. 10. Isoproterenol dose–response relation in the conscious state and during propofol anesthesia after U46619 preconstriction. Vasodilator response to isoproterenol is expressed as the percentage decrease in U46619 preconstriction. Isoproterenol-induced pulmonary vasodilation is similar in the conscious and propofol-anesthetized states. PAP-LAP = pulmonary arterial pressure–left atrial pressure.