Author + information
- Received July 20, 1994
- Revision received November 18, 1994
- Accepted November 29, 1994
- Published online April 1, 1995.
- Morihito Okada, MDa,b,c,*,
- Chojiro Yamashita, MDa,b,c,
- Masayoshi Okada, MDa,b,c and
- Kenji Okada, MDa,b,c
- ↵*Address for correspondence: Dr. Morihito Okada, Department of Surgery, Division II, Kobe University School of Medicine, Kusunoki-cho 7-5-2, Chuo-ku, 650 Kobe City, Japan.
Objectives. This study investigated the pharmacologic effect of endothelin receptor antagonists on cardiopulmonary hemodynamic variables in a beagle model of pulmonary hypertension.
Background. We recently developed a beagle model of pulmonary hypertension that allows accurate determination of cardiopulmonary hemodynamic variables and is associated with elevated plasma endothelin-1 concentrations similar to those in pulmonary hypertension in humans.
Methods. Twelve beagles (pulmonary hypertension, n = 6; control group, n = 6) were studied during baseline conditions and during right atrial infusion of FR139317 (an ETA receptor antagonist), RES-701-1 (an ETB receptor antagonist), nitroglycerin and prostaglandin E1. Pulmonary hypertension was induced in experimental beagles 8 weeks after injection with 3 mg/kg body weight of dehydromonocrotaline.
Results. FR139317 lowered pulmonary artery and systemic arterial pressures in both pulmonary hypertensive and control beagles, with a significantly greater effect on pulmonary artery pressure in pulmonary hypertensive dogs. RES-701-1 tended to increase pulmonary artery pressure only in pulmonary hypertensive beagles. Nitroglycerin depressed pulmonary artery and systemic arterial tone equally well in control and pulmonary hypertensive animals. Prostaglandin E1produced a greater decrease in systemic arterial pressure in pulmonary hypertensive than in normal beagles despite having the same effect on pulmonary artery pressure in both.
Conclusions. ETA receptor antagonists decrease pulmonary artery pressure in a beagle model and may therefore be clinically useful for treatment of pulmonary hypertension.
- Received July 20, 1994.
- Revision received November 18, 1994.
- Accepted November 29, 1994.
- North American Society of Pacing and Electrophysiology; American College of Cardiology; American Heart Association, Inc.; and European Society of Cardiology.