title: Demonstration of alpha 1s-adrenoceptors after exposure of the rat anococcygeus to benextramine.
abstract: Sgd 101/75 (4(2-imidazoline-amino)-2-methylindazol-chlorhydrate) and noradrenaline exerted similar, full agonist effects on the alpha-adrenoceptors of the rat anococcygeus. Benextramine (30 microM for 30 min, followed by 20 washes over 30 min) abolished contractions of the anococcygeus to Sgd 101/75, but only reduced those to noradrenaline. Sgd 101/75 (400 microM) did not significantly reduce contractions of the benextramine-treated (30 microM) anococcygeus to noradrenaline. It is concluded that benextramine can replace phenoxybenzamine as the alkylating agent in the demonstration of alpha 1s-adrenoceptors in the rat anococcygeus.
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D003000:Clonidine / Q000031:analogs & derivatives / Q000494:pharmacology; D003538:Cystamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009132:Muscles / Q000032:analysis*; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000032:analysis*
chemical_list: D000317:Adrenergic alpha-Antagonists; D011942:Receptors, Adrenergic, alpha; C029998:benextramine; D003000:Clonidine; C034204:indanidine; D003538:Cystamine; D009638:Norepinephrine