The isolated human epicardial coronary artery.
Ring segments from coronary arteries from recipient hearts of patients receiving cardiac transplants were prepared and mounted in an organ bath. Spontaneous contractile activity, factors that affect basal tone, agonist-induced contractile responses, regional receptor distribution, activity of cardioactive drugs, and species differences were studied. Agents that mediate contraction include histamine, acetylcholine, norepinephrine, potassium and some prostaglandins. Calcium-entry blockers, nitrates and beta-adrenergic agonists caused relaxation. Major species differences exist in coronary vascular pharmacology. Ring segments from human epicardial coronary arteries are suitable for pharmacologic studies, and because of species differences, they offer an ideal model for investigating the pharmacology of the human coronary circulation.
D000818:Animals; D001158:Arteries / Q000033:anatomy & histology / Q000187:drug effects; D003331:Coronary Vessels / Q000033:anatomy & histology / Q000187:drug effects*; D006801:Humans; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects; D009129:Muscle Tonus / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D010496:Pericardium / Q000033:anatomy & histology; D013045:Species Specificity