β‐Adrenoceptor Profile of Ractopamine HCl in Isolated Smooth and Cardiac Muscle Tissues of Rat and Guinea‐pig

@article{Colbert1991AdrenoceptorPO,
  title={$\beta$‐Adrenoceptor Profile of Ractopamine HCl in Isolated Smooth and Cardiac Muscle Tissues of Rat and Guinea‐pig},
  author={Walter E. Colbert and P. D. Williams and Gail D. Williams},
  journal={Journal of Pharmacy and Pharmacology},
  year={1991},
  volume={43}
}
Abstract— The investigational sympathomimetic amine, ractopamine hydrochloride, has been profiled for adrenergic activity in selected smooth and cardiac muscle preparations. There was no significant interaction of ractopamine with α‐adrenergic receptors in the rat vas deferens at concentrations up to 10−5 m. However, ractopamine produced a concentration‐dependent increase in the force and rate of contractions of atria isolated from normal and reserpinized guinea‐pigs (EC50= 1 × 10−7 m). These… 

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