Contrasting effects of betaxolol and propranolol on Ca2+-activated contractions in skinned fibers from canine coronary arteries and ventricular muscles

  title={Contrasting effects of betaxolol and propranolol on Ca2+-activated contractions in skinned fibers from canine coronary arteries and ventricular muscles},
  author={Yoshimi Kitada},
  journal={Cardiovascular Drugs and Therapy},
  • Y. Kitada
  • Published 1 November 1996
  • Biology
  • Cardiovascular Drugs and Therapy
SummaryThe effects of some beta-adrenoceptor antagonists (atenolol, betaxolol, bunitrolol, labetalol, pindolol, and propranolol) on Ca2+ (pCa 5.8)-activated tension development in chemically skinned fibers from canine coronary artery and right ventricular trabeculae were studied. In skinned coronary arteries, Ca2+-activated tension development was decreased by betaxolol and propranolol at concentrations of more than 10−5 and 10−4 M, respectively. The pCa-tension relationships were shifted to… 
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