The effect of D2343 in transmurally stimulated rabbit isthmus muscle.
In in vitro experiments spirally cut isthmic preparations from oestrogenized rabbits have been contracted by transmural stimulation. The beta 2-agonistic and alpha 1-antagonistic drug D2343 (for chemical structure, see fig. 1 in Olsson et al. 1984) inhibits the evoked contractions in a concentration related fashion with 50% effect at 9.6 X 10(-6) mol/l. The alpha 1-antagonist prazosin has an inhibiting action in the same concentration range (EC50 = 14.0 X 10(-6) mol/l). To inhibit the contractile response to the same degree by the beta 2-agonist terbutaline the concentration has to be greater than 10(-3) mol/l. From received results the beta (beta 2)-adrenoceptor mediated effects seem to be of minor importance compared to the alpha (alpha 1)-receptor dominance in the isthmus muscle during oestrus.
Olsson
O A
OA
Gustafsson
B
B
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005187:Fallopian Tubes / Q000187:drug effects* / Q000502:physiology; D005260:Female; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects*; D009655:Octopamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology; D011817:Rabbits; D013726:Terbutaline / Q000494:pharmacology
D000317:Adrenergic alpha-Antagonists; D000318:Adrenergic beta-Agonists; D009655:Octopamine; C033651:D 2343; D013726:Terbutaline; D011224:Prazosin