Adrenergic Agonists

Question 1

Norepinephrine (Levophed)

Answer 1

Potent vasoconstrictor and inotropic agent

L-isomer much more potent than d-isomer

More α than B activity

α activity produces increased peripheral vascular resistance, and increased systemic BP and increased coronary artery blood flow

Some B1 activity: in lower doses, B1 cardiac stimulatory effects are seen

but with larger doses, vasoconstrictive effects (α1) are predominate cause of increased BP

Like other catacholamines, NE increases cAMP in cells via B stimulation, and decreased cAMP via α stimulation