目的：研究去甲肾上腺素（ＮＥ）介导大鼠肠系膜血管床（ＭＶＢ）收缩的α１肾上腺素受体（α１ＡＲ）亚型．方法：用灌流大鼠ＭＶＢ标本收缩功能实验和克隆细胞放射配体结合实验测定α１ＡＲ亚型选择性拮抗剂ｐＡ２和ｐＫｉ，并作相关分析．结果：α１ＡＡＲ选择性拮抗剂ＲＳ１７０５３、ＷＢ４１０１、５ＭＵ及α１ＤＡＲ选择性拮抗剂ＢＭＹ７３７８的ｐＡ２分别为８９８±０２８，９１６±０２０，８．６９±００２和６０３±０２６，Ｓｃｈｉｌｄ作图斜率值与１０差别无显著性．其ｐＡ２值与α１ＡＡＲ的ｐＫｉ相关系数为０９７，与α１Ｂ和α１ＤＡＲ的相关系数分别为０５２和００４．结论：介导外源性ＮＥ收缩大鼠ＭＶＢ的功能性受体为α１ＡＡＲ Objective: To investigate the effect of norepinephrine (NE) on α1adrenoceptor (α1AR) subtype in rat mesenteric vascular bed (MVB). METHODS: The α1AR subtype selective antagonists pA2 and pKi were determined by the contractile function of MVB specimens and the radioligand binding assay of the cloned cells. The correlation analysis was performed. Results: The pA2 of α1AAR selective antagonist RS17053, WB4101,5MU andα1DAR selective antagonist BMY7378 were898 ± 0.28,916 ± 0.20,8.69 ± 002 and 603 ± 026, Schild plot slope value and 1  0 difference was not significant. The pA2 value of pA2 and α1AAR were 0.97 for pKi and 052 and 0.04 for α1Band α1DAR, respectively. CONCLUSIONS: The functional receptor mediating MVB in exogenous NE-contracted rats is α1AAR