Inhibition of Constrictor Responses of Dog Coronary Artery by Atropine A Possible Effectiveness of Atropine on Variant Form of Angina Pectoris

• Published in: Japanese Heart Journal Vol. 20; no. 1; pp. 75 - 82
• Main Authors: SAKANASHI, Matao, FURUKAWA, Terutsugi, HORIO, Yutaka
• Format: Journal Article
• Language: English
• Published: Japan International Heart Journal Association 1979
• Subjects: Acetylcholine; Acetylcholine - antagonists & inhibitors; Adrenergic alpha-receptor; Angina Pectoris - drug therapy; Angina Pectoris, Variant - drug therapy; Animals; Arteries - drug effects; Atropine - pharmacology; Atropine - therapeutic use; Contractions of coronary artery; Coronary Vessels - drug effects; Dogs; Female; In Vitro Techniques; Male; Muscarinic receptor; Norepinephrine; Norepinephrine - antagonists & inhibitors; Vasoconstriction - drug effects
• ISSN: 0021-4868; 1348-673X
• DOI: 10.1536/ihj.20.75

A possible effectiveness of atropine on variant form of angina pectoris was investigated using the left circumflex coronary arterial strips of dogs. Acetylcholine 10-5-10-3Gm/ml dose-dependently constricted the isolated arterial strips during potassium-contracture in 6 cases, and repetitive applications of acetylcholine could produce the similar contractions to the control. In 18 strips atropine 10-6Gm/ml significantly depressed the contractions of coronary arteries induced by acetylcholine 10-5-10-3Gm/ml. In 5 arterial strips atropine 10-6Gm/ml significantly inhibited norepinephrine-induced responses of these arteries, and by 10-5Gm/ml further suppression of these responses was obtained. The results suggest that atropine may suppress the contractile responses of the coronary artery induced by acetylcholine and norepinephrine through a muscarinic-receptor blocking action and simultaneously partly through an adrenergic alpha-receptor blocking action.