Beta adrenergic and muscarinic cholinergic receptors in canine myocardium. Effects of ischemia.

Abstract

Experimental myocardial ischemia produced in dogs by proximal left anterior descending coronary artery ligation is accompanied by relatively rapid (1 h) increases in the number of (-) [3H]dihydroalprenolol binding sites without changing their dissociation constants in ischemic left ventricular tissue. The changes, persist for at least 8 h and are accompanied by marked decreases in myocardial tissue ischemic region norepinephrine content. In contrast, in the same canine model 1 h of proximal left anterior descending coronary artery ligation did not result in a significant change in the number of [3H]quinuclidynl benzilate binding sites of their dissociation constants. However, the number of [3H]quinuclidynl benzilate binding sites (muscarinic cholinergic receptors) are 50--70% greater than (-) [3H]dihydroalprenolol binding sites (beta adrenergic receptors) in canine left ventricular tissue. Thus, the data suggest that proximal left anterior descending coronary artery occlusion for 1 h significantly increases the number of beta adrenergic receptors in ischemic left ventricular tissue without changing the number of muscarinic cholinergic receptors. Whether the ischemia-produced increase in cardiac beta-receptor content is causally related to increased cyclic AMP levels that develop in ischemic tissue and/or an etiologic factor in arrhythmias originating from ischemic myocardial tissue will have to be determined in additional studies.

• Authors: A Mukherjee, T M Wong, L M Buja, R J Lefkowitz, J T Willerson
• Journal: The Journal of clinical investigation (J Clin Invest) Vol. 64 Issue 5 Pg. 1423-8 (Nov 1979) ISSN: 0021-9738 [Print] United States
• PMID: 227935 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Receptors, Adrenergic
• Receptors, Adrenergic, beta
• Receptors, Cholinergic
• Receptors, Muscarinic
• Dihydroalprenolol
• Quinuclidinyl Benzilate
• Norepinephrine

Topics

• Animals
• Coronary Disease (metabolism)
• Coronary Vessels (surgery)
• Dihydroalprenolol (metabolism)
• Dogs
• Female
• Ligation
• Male
• Myocardium (metabolism)
• Norepinephrine (metabolism)
• Quinuclidinyl Benzilate (metabolism)
• Receptors, Adrenergic (isolation & purification)
• Receptors, Adrenergic, beta (isolation & purification, metabolism)
• Receptors, Cholinergic (isolation & purification)
• Receptors, Muscarinic (isolation & purification, metabolism)