studies in isolated preparations dealing with myocardial effects of catecholamines usually employ epinephrine concentrations 10-1,000 times higher ( 10 ( -7 ) -10 ( -5 ) m ) than those observed during maximal cardiac adrenoceptor activation in vivo ( 10 ( -9 ) -5 x 10 ( -8 ) m ) to obtain measurable cardiac responses .
C0027061
myocardial
C0018787
cardiac