Trifluoperazine antagonizes postsynaptic alpha 1-but not alpha 2-adrenoceptor-mediated pressor responses in the rat.
The specificity of the alpha-adrenergic blockade by trifluoperazine was tested in pithed rats. Trifluoperazine reduced the pressor effects of (-)-noradrenaline. The log dose-response curve to methoxamine, an alpha 1-agonist, was shifted to the right whereas the vasopressor responses to BHT-920, an alpha 2-agonist, were unaffected by trifluoperazine. It was concluded that trifluoperazine acts as a peripheral vascular alpha 1-antagonist in the rat.
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D001381:Azepines / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D014268:Trifluoperazine / Q000494:pharmacology*
D000317:Adrenergic alpha-Antagonists; D001381:Azepines; D011942:Receptors, Adrenergic, alpha; D014268:Trifluoperazine; C024763:talipexole