[Effects of beraprost sodium (a PGI2 derivative) on chronic hypoxic pulmonary hypertension in the rat].
To determine whether beraprost sodium (beraprost) can cause pulmonary vasodilation in chronic hypoxic pulmonary hypertension, we measured the hemodynamic effects of intravenous beraprost, a stable and orally active agent with a PGI2-like structure, in chronic hypoxic (H) and normoxic (N) rats. During anesthesia baseline pulmonary artery pressure (PAP) was 32.0 +/- 1.0 in H rats and 18.0 +/- 0.4 mmHg in N rats. Intravenous beraprost (20 micrograms/kg) elicited acute pulmonary vasodilation by 17.7 +/- 4.6% (5.6 +/- 1.4 mmHg) in H rats and by 16.8 +/- 2.1% (3.0 +/- 0.6 mmHg) in N rats, which indicates that the relative degree of acute pulmonary vasodilation caused by beraprost was similar in H and N rats. Thirty minutes after the drug was injected, PAP had not returned to baseline levels in either H or N rats, and it was lower in H rats (90 +/- 2%) than in N rats (95 +/- 2%). Lungs were isolated and perfused with saline, and those from H rats and N rats showed similar pulmonary vasodilator responses to 2 and 20 micrograms/kg beraprost. These results indicate that although beraprost caused a similar degree of acute pulmonary vasodilation in H and N rats, in H rats the response lasted longer. Thus PGI2 derivatives may be useful as vasodilators in some patients with primary and secondary pulmonary hypertension.
Saito
M
M
Department of Chest Medicine, School of Medicine, Chiba University, Japan.
Tatsumi
K
K
Kasahara
Y
Y
Tani
T
T
Kuriyama
T
T
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D011464:Epoprostenol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000503:physiopathology; D000860:Hypoxia / Q000150:complications; D066298:In Vitro Techniques; D008297:Male; D011651:Pulmonary Artery / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D014664:Vasodilation / Q000187:drug effects
C048081:beraprost; D011464:Epoprostenol