Possible Interaction: Ketanserin and Yohimbine

“Also, ketanserin further increased FBF after vasodilation of reflexly vasoconstricted fingers by the alpha 2-adrenoceptor antagonist, yohimbine , and phentolamine increased FBF during ketanserin infusions.”

“On a background of treatment with the α2-adrenoceptors blocker yohimbine (0.5 mg/kg), mianserin, cyproheptadine, and ketanserin inhibited movement activity and significantly reduced the sensitivity of animals to audiogenic convulsions.”

“… ketanserin … yohimbine or rauwolscine antagonized the 5HT effects as expected from competition of all 4 drugs for a single class of receptors in pulmonary arteries.5.… low (≤ 10−7 mol/l) in humans to account for a contribution of the metabolite to the blockade of 5HT effects by ketanserin.”

“Combinations of rauwolscine or yohimbine with ketanserin antagonized the 5 HT effects as expected from competition of the 4 drugs for a single class of receptor.4.The evidence is consistent with an interaction of 5 HT, ketanserin, rauwolscine and yohimbine with 5 HT2 receptors.”

“Prazosin (0.1 microM) did not affect inhibition of the MSR but yohimbine (1 microM) blocked it as effectively as ketanserin.”

“The responses after 5HT and NA stimulation were blocked to baseline levels after exposure to ketanserin (5HT2 receptor antagonist) and a combination of prazosin, yohimbine , and propranolol (α1, α2, and β adrenoceptor antagonists, respectively).”

“This response to yohimbine (3 X 10(-7) M) was attenuated by 5-HT receptor antagonists such as 5-methoxygramine, methysergide and ketanserin.”

“Thus, the abilities of yohimbine to inhibit and ketanserin to abolish cyclic flow reductions in stenosed canine coronary arteries suggest that serotonin and, possibly, alpha 2-adrenergic agonists may influence cyclic flow alterations importantly in this model.”