【摘要】 研究大鼠不同血管中α１ 肾上腺素受体（α１ａｄｒｅｎｏｃｅｐｔｏｒ，α１ＡＲ） 亚型的分布情况及其功能意义。方法：采用离体血管收缩功能实验，测定α１ＡＲ 选择性拮抗剂抑制大鼠血管ＮＥ收缩反应的功能性亲和常数（ｐＡ２） ，与分别表达α１Ａ、α１Ｂ和α１ＤＡＲ的克隆细胞上结合常数（ｐＫｉ）作相关性分析，以判断血管中的α１ＡＲ 亚型分布。结果：哌唑嗪、ＷＢ４１０１ 、５ＭＵ、ＢＭＹ７３７８ 和ＲＳ１７０５３ 分别竞争性地抑制血管对ＮＥ 的收缩效应，ｐＡ２ 值与这些拮抗剂对克隆α１Ａ、α１Ｂ、α１ＤＡＲ 的ｐＫｉ 值间的决定系数在肺动脉分别为０ ．０５、０．４５、０．７７ ；在肠系膜动脉分别为０．０２、０．４７ 、０ ．８７ ；在尾动脉分别为０ ．７７ 、０ ．７７ 、０ ．４４ ；在门静脉分别为０ ．７９ 、０ ．８１、０ ．２７。结论：大鼠肺动脉、肠系膜动脉的功能性α１ＡＲ主要为α１ＤＡＲ；而尾动脉与门静脉的功能性α１ＡＲ主要是α１Ａ和α１Ｂ亚型。更多还原

【Abstract】 Objective: The distribution of three α 1 adrenoceptor(α 1 AR) subtypes and their functional roles in rat different vessels was investigated. Methods: The effects of α 1 AR subtype selective antagonists on norepinephrine (NE) induced contraction were observed by in vitro contractile studies. And correlation analysis between pA 2 value of α 1 AR selective antagonists in functional experiments and binding pK i value in cloned α 1 AR subtypes expressed in HEK293 cells was used to characterize the distribution of α 1 AR subtype in rat vessels. Results: Cumulative concentration contractile response curves (CRC) for NE were competitively antagonized in rat pulmonary artery, mesenteric artery , caudal artery and portal vein by prazosin, WB4101, 5 MU, RS17053 and BMY7378. CEC shifted the NE CRC to the right and reduced the maximal contraction response in these vessels. The coefficients of determination with α 1A , α 1B and α 1D AR in pulmonary artery were 0.05,0.45 and 0.77; in mesenteric artery 0.02, 0.47 and 0.87; in caudal artery and portal vein 0.77,0.77,0.44 and 0.79, 0.81,0.27 respectively. Conclusion: The functional α 1 AR in rat pulmonary artery and mesenteric artery is mainly α 1D AR, and in rat caudal artery and portal vein mainly α 1A and α 1B AR.更多还原