Exercise training does not alter acetylcholine-induced responses in isolated pulmonary artery from rat

• Published in: The European respiratory journal Vol. 13; no. 3; pp. 622 - 625
• Main Authors: Mitani, Y, Maruyama, J, Maruyama, K, Sakurai, M
• Format: Journal Article
• Language: English
• Published: Leeds Eur Respiratory Soc 01.03.1999; Maney
• Subjects: Acetylcholine - pharmacology; Animals; Biological and medical sciences; Cardiomegaly - physiopathology; Cardiovascular system; Culture Techniques; Dinoprost - pharmacology; Disease Models, Animal; Investigative techniques of hemodynamics; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Muscle, Smooth, Vascular - drug effects; Muscle, Smooth, Vascular - physiology; Nitric Oxide - metabolism; Nitroprusside - pharmacology; Physical Conditioning, Animal; Potassium Chloride - pharmacology; Pulmonary Artery - drug effects; Pulmonary Artery - physiology; Rats; Rats, Sprague-Dawley; Sensitivity and Specificity; Vasodilation - drug effects; Vasodilation - physiology; Vasodilator Agents - pharmacology; Treadmill exercise; Pharmacologic test; Physical training; Rat; Rodentia; Exploration; Pulmonary artery; Endothelium; Isolated organ; Sodium nitroprusside; Vertebrata; Vasomotricity; Mammalia; Animal; Nitric oxide; Acetylcholine; Hemodynamics
• ISSN: 0903-1936; 1399-3003
• DOI: 10.1183/09031936.99.13362299

In chronic exercise-trained animals, acetylcholine (ACh)-stimulated endothelial nitric oxide (NO) release is enhanced in the systemic circulation. The purpose of the present study was to determine whether chronic exercise training also enhances NO-mediated relaxation in rat pulmonary artery. Sprague-Dawley rats were randomly divided into groups of exercise-trained and sedentary control rats. The exercise-trained rats ran on a motor-driven treadmill at 30 m x min(-1) up a 15 degree incline 10-60 min x day(-1), 5 days per week for 10 weeks, and had less body weight, lower serum total cholesterol and triglyceride levels than sedentary rats. Contraction induced by potassium chloride and prostaglandin (PG)F2alpha were similar between isolated conduit pulmonary arterial rings from sedentary and exercise-trained rats. There were no differences between PGF2alpha-precontracted rings from sedentary and exercise trained rats in both ACh and sodium nitroprusside-induced relaxations. The NO synthase inhibitor, nitro-L-arginine, suppressed ACh-induced relaxation in both sedentary and exercise-trained rats. These results suggested chronic exercise training did not alter the acetylcholine-induced endothelial NO production and release and the sensitivity of vascular smooth muscle cell to NO in isolated conduit pulmonary artery of rat.