几种α(1)和α(2)肾上腺素能受体亚型在犬颈外动脉循环中介导血管收缩的作用。

The role of several alpha(1)- and alpha(2)-adrenoceptor subtypes mediating vasoconstriction in the canine external carotid circulation.

Willems E W, Valdivia L F, Saxena P R, Villalón C M

Department of Pharmacology, Erasmus University Medical Centre Rotterdam, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands.

Br J Pharmacol. 2001 Mar;132(6):1292-8. doi: 10.1038/sj.bjp.0703915.

It has recently been shown that both alpha(1)- and alpha(2)-adrenoceptors mediate vasoconstriction in the canine external carotid circulation. The present study set out to identify the specific subtypes (alpha(1A), alpha(1B) and alpha(1D) as well as alpha(2A), alpha(2B) and alpha(2C)) mediating the above response. 2. Consecutive 1 min intracarotid infusions of phenylephrine (alpha(1)-adrenoceptor agonist) and BHT933 (alpha(2)-adrenoceptor agonist) produced dose-dependent decreases in external carotid blood flow, without affecting mean arterial blood pressure or heart rate. 3. The responses to phenylephrine were selectively antagonized by the antagonists, 5-methylurapidil (alpha(1A)) or BMY7378 (alpha(1D)), but not by L-765,314 (alpha(1B)), BRL44408 (alpha(2A)), imiloxan (alpha(2B)) or MK912 (alpha(2C)). In contrast, only BRL44408 or MK912 affected the responses to BHT933. 4. The above results support our contention that mainly the alpha(1A), alpha(1D), alpha(2A) and alpha(2C)-adrenoceptor subtypes mediate vasoconstriction in the canine external carotid circulation.

最近的研究表明，α(1)-和α(2)-肾上腺素能受体均介导犬颈外循环中的血管收缩。本研究旨在确定介导上述反应的特定亚型（α(1A)、α(1B)和α(1D)以及α(2A)、α(2B)和α(2C)）。2. 连续1分钟颈内输注去氧肾上腺素（α(1)-肾上腺素能受体激动剂）和BHT933（α(2)-肾上腺素能受体激动剂）可使颈外血流呈剂量依赖性减少，而不影响平均动脉血压或心率。3. 去氧肾上腺素的反应被拮抗剂5-甲基尿嘧啶（α(1A)）或BMY7378（α(1D)）选择性拮抗，但不受L-765,314（α(1B)）、BRL44408（α(2A)）、咪咯生（α(2B)）或MK912（α(2C)）影响。相反，只有BRL44408或MK912影响对BHT933的反应。4. 上述结果支持我们的观点，即主要是α(1A)、α(1D)、α(2A)和α(2C)-肾上腺素能受体亚型介导犬颈外循环中的血管收缩。

The role of several alpha(1)- and alpha(2)-adrenoceptor subtypes mediating vasoconstriction in the canine external carotid circulation.