Potencies for different receptors


These 4 graphics show the potencies of 3 agonists (adrenaline, noradrenaline, isoprenaline) for the different adrenergic receptors.


The potency of the 3 agonists for the α1 and α2 receptors is similar:

  • Adrenaline and noradrenaline are equally potent for both receptors
  • Isoprenaline is less potent for both receptors.



The 3 agonists display different potency patterns for β1 and β2 receptors:

  • Isoprenaline is the most potent for both β1 and β2.
  • For the β1 receptor adrenaline and noradrenaline are both less potent than isoprenaline, but with about the same ED50.
  • For the β2 receptor, noradrenaline is the least potent of all 3 agonists and adrenaline has intermediate potency.