Adrenergic Agonists

Catecolamines
1. Rapid inactivation (COMT/MAO), cannot be taken orally. Poor CNS penetration.
  1. Epinephrine, Norpeinephrine, Dopamine
Affects sympathetic NS through adrenoreceptors
Non-catecolamines
1. Long half-life (slow MAO), can be taken orally. Penetration into CNS.
  1. Ephedrine
Direct acting
1. Epinephrine
  1. Alpha1, 2 Beta 1, 2
    1. Alpha 1 (vasoconstriction) – delays absorption of anaesthetics, control superficial bleeding, increase BP Beta 1 – overcome AV heart. Beta 2 – bronchodilation
      1. Hypersensitive crisis (↑ BP), Dysrhythmias, Angina Pectoris, Hyperglycaemia
2. Dopamine
  1. Alpha and Beta
    1. Cardiogenic and septic shock, raises BP and increases cardiac output. Enhances kidney and splancnic perfusion
Indirect acting
1. Amphetamines
  1. Enhance E and EN
    1. Stimulatory (E/NE), increase BP through release of Dopamine and NE
Mixed
1. Ephidrine
  1. Release stored NE and stimulate α and β receptors. Vasoconstriction, bronchodilation.
1. Direct receptor binding
2. Promote NE release
3. Inhibit NE reuptake
4. Inhibition of NE inactivation (MAO)
Receptors
1. α1
  1. Eyes, blood vessels, male sex organs, prostatic capsule, bladder
2. α2
3. β1
  1. Heart, kidney
4. β2
  1. Blood vessels, bronchi, GIT, liver, skeletal muscle

Resource summary

	Created by Lindie Metz about 8 years ago