the vasoconstrictor responses to the selective alpha 2-adrenergic receptor agonist tl99 or to phenylephrine were also antagonized by low concentrations of idazoxan . in contrast , idazoxan did not antagonize responses induced by the alpha 1-adrenergic receptor agonists amidephrine or methoxamine in perfused tail arteries of shr .
C0031469
phenylephrine
C1373109
alpha