these data indicate that in the intact human heart endomyocardial biopsy may be used for direct analysis of beta-adrenergic receptors , heart failure-associated myocardial beta-adrenergic down-regulation begins with mild-moderate ventricular dysfunction , reduction in myocardial beta-receptor density is related to degree of heart failure , and beta-receptor down-regulation is associated with pharmacologically specific impairment of the beta-agonist-mediated contractile response .
C0018787
heart
C0027061
myocardial