论文部分内容阅读
目的：探讨门静脉α肾上腺素受体及亚型的分布及其对门脉循环的调控机制。方法：采用药理受体分析方法，结合离体和整体实验，测定α肾上腺素受体拮抗剂和激动剂应用前后；ｐＡ２，ｐＤ２，ＥＣ５０，Ｒｍａｘ和门静脉压力（ＰＶＰ）。结果：①ＮＥ浓度－收缩曲线均右移，程度为哌唑嗪（Ｐｒａ）４０倍，硝苯吡啶（Ｎｉｆ）２３１．８倍，育亨宾（Ｙｏｈ）４．２倍。②对Ｒｍａｘ的抑制率：Ｎｉｆ８９．１％，Ｐｒａ７１．２％，Ｙｏｈ４１．９％。③与门静脉α受体亲和力（ｐＡ２）：Ｐｒａ８．１９，Ｙｏｈ６．０９，Ｎｉｆ６．０２。④对ＰＶＰ影响：苯福林（Ｐｈｅ）显著升高ＰＶＰ（Ｐ＜０．０５），Ｐｒａ和Ｎｉｆ显著降低ＰＶＰ（Ｐ＜０．０１）。结论：大鼠静脉α受体亚型分布α１亚型，而α１受体亚型构成中主要以α１ａ为主。它们介导门静脉的收缩效应，调节门脉循环。
Objective: To investigate the distribution of α-adrenergic receptors and subtypes in the portal vein and their regulatory mechanisms on portal circulation. METHODS: Pharmacological receptor assays were used in combination with in vitro and in vivo experiments to determine the levels of pA2, pD2, EC50, Rmax and portal pressure (PVP) before and after the administration of α-adrenergic receptor antagonists and agonists. Results: ① The concentration and contraction curve of NE both shifted to the right, which was 40 times higher than that of Pra, 231.8 times of Nif and 4.2 times of Yoh. The inhibitory rate of Rmax: Nif89.1%, Pra71.2%, Yoh41.9%. ③ and portal vein α receptor affinity (pA2): Pra8.19, Yoh6.09, Nif6.02. (4) Effects on PVP: Phe significantly increased PVP (P <0.05), while Pra and Nif decreased PVP significantly (P <0.01). Conclusion: The α subtype is distributed in the vein of rats, while α1a is the main component in the α1 subtype. They mediate the contractile effect of the portal vein and regulate the portal circulation.