β‐Adrenergic activities of octopamine and synephrine stereoisomers on guinea‐pig atria and trachea

@article{Jordan1987AdrenergicAO,
  title={$\beta$‐Adrenergic activities of octopamine and synephrine stereoisomers on guinea‐pig atria and trachea},
  author={Roy Jordan and John M. Midgley and C. Mohan Thonoor and C. M. Williams},
  journal={Journal of Pharmacy and Pharmacology},
  year={1987},
  volume={39}
}
The activities of the (‐)‐ and (+)‐forms of m‐ and p‐octopamine and m‐ and p‐synephrine on β1‐ and β2‐ adrenoceptors in guinea‐pig atria and trachea have been compared with that of noradrenaline. The rank order of potency of the (‐)‐forms on β1‐adrenoceptors was noradrenaline > m‐synephrine. m‐octopamine = p‐octopamine > p‐synephrine. m‐Synephrine was 100‐fold, m‐and p‐octopamine about 6000‐fold, and p‐synephrine about 40 000‐fold less active than noradrenaline. The (+)‐forms were 1‐2 orders of… 
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