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用离休血管收缩功能实验法分析了大鼠基底动脉（ＢＡ）、肺动脉（ＰＡ）和尾动脉（ＣＡ）血管紧张素Ⅱ（ＡⅡ）受体ＡＴ１和ＡＴ２亚型的组成及各自的功能意义。结果表明，ＢＡ对ＡⅡ无收缩反应，提示在ＢＡ可能不表达ＡＴ１亚型，或表达极微。在ＢＡ有ＡＴ２亚型分布，通过内皮－ＮＯ－ｃＧＭＰ途径（而不是环氧合酶依赖性途径）介导ＢＡ对ＡⅡ的内皮依赖性舒张反应。在ＰＡ和ＣＡ均存在着ＡＴ１亚型，介导ＰＡ和ＣＡ对ＡⅡ的收缩反应。但ＰＡ的ＡＴ１亚型具有亲和力高、易脱敏的特点，提示该ＡＴ２亚型可能不同于存在于ＣＡ的ＡＴ１亚型。
The composition and their functional significance of AT1 and AT2 subtypes of angiotensin Ⅱ (AⅡ) receptor in basilar artery (BA), pulmonary artery (PA) and tail artery (CA) The results showed that no contractile response of BA to AⅡ, suggesting that BA may not express AT1 subtype, or minimal expression. AT2 subtype distribution in BA mediates the endothelium-dependent vasorelaxation of AII by BA via the endothelial-NO-cGMP pathway, but not the cyclooxygenase-dependent pathway. There are AT1 subtypes in both PA and CA, mediating the contractile response of PA and CA to AII. However, the AT1 subtype of PA has the characteristics of high affinity and easy desensitization, suggesting that the AT2 subtype may be different from the AT1 subtype existing in CA.