Possible Interaction: Epinephrine and Prazosin

“The pharmacological blockade of α1-adrenergic receptor by prazosin synergistically potentiated such mast cell-stabilizing property of adrenaline , which is primarily mediated by β2-adrenergic receptors.”

“The effects of epinephrine and norepinephrine were inhibited by prazosin (&agr;1 antagonist) and by yohimbine (&agr;2 antagonist), while dopamine's were inhibited only by prazosin.”

“In both preparations lysine-vasopressin (LVP) and epinephrine (EPI) stimulated ACTH secretion; prazosin (alpha-1 blocker) inhibited the EPI but not the LVP-mediated stimulation.”

“In 1995 I encountered a problem with the use of adrenaline in the resuscitation of a patient on prazosin who had an anaphylactic collapse resulting from a bee sting.”

“In contrast, alpha 1-adrenergic blockade with unlabelled prazosin restored the effect of T4 on Ca(2+)-ATPase activity in the presence of epinephrine.”

“ Prazosin induced a 2.4-fold (+/- 0.5) shift in the responses to epinephrine and a 4.5-fold (+/- 1.2) shift in the response to phenylephrine (p less than 0.05).”

“The effect of (−)‐adrenaline was potently inhibited by prazosin , a potent and selective α1‐adrenoceptor antagonist, but not by yohimbine, a selective α2‐adrenoceptor antagonist.”

“… epinephrine , phenylephrine, or methoxamine …-adrenoceptor antagonists (eg, prazosin ), α1, α2-adrenoceptor antagonist, α1A-adrenoceptor antagonist (eg, 5-methylurapdil), α1B-adrenoceptor antagonist (eg, chloroethylclonidine), or α1D-adrenoceptor antagonist (eg, BMY7873).… epinephrine, phenylephrine and methoxamine all act mainly via mixed subtypes of α1-adrenoceptors to induce cutaneous anesthesia in the rat.”

“Phentolamine (3.55 x 10(-5) M), prazosin (2.38 x 10(-5) M) and yohimbine (2.821 x 10(-5) M) significantly inhibited the aggregatory responses of the fish melanophores to adrenaline , nor-adrenaline, clonidine and phenylepherine.”

“The increase in glucose and NO(2)(-) released by epinephrine or phenylephrine was blocked or reduced by prazosin pretreatment and by NOS inhibitors aminoguanidine and L-NAME.”