Role of 2-adrenoceptors (ß-AR), but not ß1-, 详细信息    查看全文

• 作者：Fabrice Pourageaud ; Véronique Leblais ; Nadège Bellance ; Roger Marthan and Bernard Muller
• 关键词：adrenoceptor ; Rat intrapulmonary artery ; Endothelium ; Nitric oxide
• 刊名：Naunyn-Schmiedeberg's Archives of Pharmacology
• 出版年：2005
• 出版时间：July 2005
• 年：2005
• 卷：372
• 期：1
• 页码：14-23
• 全文大小：228 KB
• 刊物类别：Biomedical and Life Sciences
• 刊物主题：Biomedicine
  Pharmacology and Toxicology
  Neurosciences
  
• 出版者：Springer Berlin / Heidelberg
• ISSN：1432-1912

文摘

The aim of this study was to analyze ß-adrenoceptor (ß-AR)-mediated relaxation in rat intralobar pulmonary artery. The relaxant responses of ß-AR agonists were characterized using ß-AR antagonists in prostaglandin F₂(PGF₂)-precontracted arteries. The role of nitric oxide (NO) and endothelium in ß-AR-mediated relaxation was also investigated. Isoprenaline (a non-selective ß-AR agonist) and salbutamol (a selective ß₂-AR agonist) induced vasorelaxation. ICI 118551 (a selective ß₂-AR antagonist) antagonized the effect of both isoprenaline and salbutamol (pA₂ values of 9.57 and 9.51 respectively). In contrast, atenolol (1 M) and CGP 20712A (0.1 M), two ß₁-AR antagonists, did not modify the relaxing effect of isoprenaline. The response to isoprenaline obtained in the presence of nadolol (10 M, a ß₁/ß₂-AR antagonist) was not further inhibited by SR 59230A (1 M, a selective ß₃-AR antagonist). The non-ß₁/ß₂-AR agonists studied (BRL 37344, SR 58611A, and CGP 12177A) did not elicit vasorelaxation. Relaxation to isoprenaline and salbutamol was unaffected by L-NG-nitro-arginine methyl ester (100 M, an inhibitor of NO synthase) or after endothelium removal. These results demonstrate the role of ß₂-AR in mediating relaxation in rat intralobar pulmonary artery precontracted with PGF₂. They indicate that ß₂-AR-mediated relaxation in this artery is NO- and endothelium-independent. Furthermore, they do not provide evidence of a relaxant role of either ß₁-or ß₃-AR in PGF₂-precontracted rat intrapulmonary artery.