Evaluation of Intrinsic Sympathomimetic Activity of Bucindolol and Carvedilol in Rat Heart

  title={Evaluation of Intrinsic Sympathomimetic Activity of Bucindolol and Carvedilol in Rat Heart},
  author={Robert Nicholas Willette and Marcus P. Mitchell and Eliot H. Ohlstein and Mary Ann Lukas and Robert R. Ruffolo Jr.},
  pages={30 - 36}
Many β-adrenoceptor antagonists are weak partial agonists, possessing significant intrinsic sympathomimetic activity (ISA). Under certain conditions, ISA may be deleterious through stimulation of β1- and/or β2-adrenoceptors in the heart. Drugs with ISA are particularly problematic in the treatment of congestive heart failure since agents that activate cardiac β-adrenoceptors, such as xamoterol, have been associated with increases in the incidence of arrhythmia and mortality. Carvedilol was… 

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