Figure 1.

Prostacyclin receptor (IP) desensitization in U46619-induced pulmonary hypertension in intact rabbit lungs in response to PGI₂ or iloprost infusion. Pulmonary hypertension was adjusted by continuous infusion of the thromboxane mimetic U46619. After a bolus injection of 200 ng iloprost followed by an infusion of 33 ng iloprost per hour (stable buffer levels of ~350 pg/ml) or continuous infusion of PGI₂ (50 ng/min) is administered and measured their influence on U46619-elicited pulmonary hypertension.