Possible Interaction: Adrenergic Alpha-Antagonists and Epinephrine

“This stimulation of GTPase activity by epinephrine is prevented in the presence of the alpha-adrenergic antagonist , phentolamine, which indicates that a functional reconstitution of the alpha 2AR and Ni has been established.”

“Its alpha-adrenergic blocking activity promotes vasodilation and antagonizes the vasoconstrictive effects of epinephrine.”

“When epinephrine is accidentally discharged into a digit, ischemic skin necrosis resulting from the alpha-adrenergic blocking effects of this agent can lead to the need for multiple operations, wound infection, and even loss of the digit.”

“This adrenaline effect could be blocked by alpha-blockers but not by beta-blockers.”

“A calcium channel blocker, verapamil, and an alpha blocker , dihydroergocryptine, effectively blocked the corrective influence of epinephrine on prostacyclin-treated platelets.”

“Blood lactate, plasma insulin, norepinephrine (NOR), and epinephrine (EPI) were increased after alpha-blockade.”

“Phentolamine (an alpha blocker) or yohimbine (an alpha 2 blocker ) administration completely inhibited the increase of glucagon secretion caused by epinephrine infusion, but neither the administration of bunazosin (an alpha 1 blocker) nor beta blockers inhibited it.”

“The decrease in arthritis induced by epinephrine (0.5 mg/kg in chronic implant injected every 3 days) was significantly antagonized by the selective alpha 2-adrenergic antagonist , yohimbine, but not by selective alpha 1 (prazosin), beta 1 (metoprolol) or beta 2 (butoxamine) antagonists.”

“Phenoxybenzamine or phentolamine alpha-adrenoceptor blockers ) only decreased the effects of adrenaline on VCL but suppressed those of noradrenaline and dopamine.”

“The non-selective agonist, adrenaline , induces a similar hyperglycemic response which is antagonized selectivity by the alpha 2-adrenoceptor antagonist , idazoxan.”