Effects of Guanosine 5'-Triphosphate on the Specificity of Irreversible α1-Antagonisms by Phenoxybenzamine in Rabbit Thoracic Aorta

[摘要] References(12)Cited-By(3)Phenylephrine displacement curves for the specific binding of [3H]prazosin in the membrane fraction prepared from rabbit thoracic aorta showed high- and low-affinity sites with slope factors significantly less than unity. The irreversible α1B-antagonist phenoxybenzamine shifted the binding sites to single high affinity sites with a slope factor close to unity in the presence of the metabolically stable GTP analog GTPγ-S. These results indicate that phenoxybenzamine may have affected selectively the low affinity site to phenylephrine in the presence of GTPγ-S.

[学科分类] 药理学

[关键词] Phenoxybenzamine;α1-Adrenoceptor subtype;G protein