Newly synthesized alpha 1-adrenoceptor blockers (SM911 and SM2470) and characterization of alpha-adrenoceptors in rat aortic strips, rat vas deferens preparations and rabbit aortic strips.
Alpha 1-adrenergic potencies of SM911 and SM2470, whose chemical structures are similar to that of prazosin, a selective alpha 1-adrenoceptor blocker, were tested in rabbit aortic strips, rat aortic strips and rat vas deferens preparations. SM2470 was as potent as prazosin in alpha 1-adrenoceptor blocking effects, though SM911 was 0.5-0.1 as potent as prazosin. The pA2-values for prazosin, SM911 and SM2470 were approximately one order of magnitude lower in rabbit aortic strips and rat vas deferens preparations than in rat aortic strips, suggesting that alpha 1-adrenoceptors in these tissues may not be identical. SM911 and SM2470 as well as prazosin did not interact with alpha 2- and beta-adrenoceptors, muscarinic and nicotinic cholinoceptors, and histamine and serotonin receptors in doses up to 10(-5) M.
Takayanagi
I
I
Konno
F
F
Arai
H
H
Chimoto
K
K
Kitada
T
T
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009130:Muscle, Smooth / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D011224:Prazosin / Q000031:analogs & derivatives* / Q000494:pharmacology; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects; D011943:Receptors, Adrenergic, beta / Q000187:drug effects; D011956:Receptors, Cell Surface / Q000187:drug effects*; D011968:Receptors, Histamine / Q000187:drug effects; D011976:Receptors, Muscarinic / Q000187:drug effects; D011978:Receptors, Nicotinic / Q000187:drug effects; D011985:Receptors, Serotonin / Q000187:drug effects; D013045:Species Specificity; D014132:Trachea / Q000187:drug effects; D014649:Vas Deferens / Q000187:drug effects
D000317:Adrenergic alpha-Antagonists; D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D011956:Receptors, Cell Surface; D011968:Receptors, Histamine; D011976:Receptors, Muscarinic; D011978:Receptors, Nicotinic; D011985:Receptors, Serotonin; C047165:SM 2470; C047164:SM 911; D011224:Prazosin