山羊脑动脉中5-羟色胺受体的特性研究

Characterization of 5-hydroxytryptamine receptors in goat cerebral arteries.

Miranda F J, Torregrosa G, Salom J B, Alabadí J A, Jover T, Barberá M D, Alborch E

Departamento de Fisiología, Universidad de Valencia, Hospital Universitario, La Fe, Spain.

Gen Pharmacol. 1995 Oct;26(6):1267-72. doi: 10.1016/0306-3623(95)00015-s.

Abstract

In isolated goat middle cerebral artery segments, 5-hydroxytryptamine (5-HT, 10(-8)-3 x 10(-5) M) elicited concentration-dependent contractions with EC50 = 2.1 (1.9-2.5) x 10(-7) M and Emax = 64 +/- 2% of 50 mM KCl-induced contraction. 2. Several 5-HT receptor agonists were used: (a) the agonist of 5-HT2 receptors alpha-methyl-5-hydroxy-tryptamine (10(-7)-3 x 10(-4) M) induced strong contraction (51 +/- 6%); (b) the selective agonists of 5-HT1 receptors sumatriptan (10(-8)-10(-5) M) and 5-carboxamidotryptamine (10(-9)-10(-4) M) and the agonist of 5-HT1A receptors 8-hydroxy-2-(di-n-propylamino)tetralin (10(-7)-3 x 10(-5) M) induced weak contractions (8, 18 and 14%, respectively); and (c) the agonist of 5HT3 receptors 2-methyl-5-hydroxytryptamine (3 x 10(-6)-10(-4) M) induced almost negligible contraction. 3. Pretreatment with the antagonist of 5-HT1A and 5-HT1B receptors cyanopindolol (10(-8), 10(-6) M), the antagonist of 5-HT1/5-HT2 receptors methysergide (10(-11), 10(-9) M) and the antagonist of 5-HT2 receptors ketanserin (10(-11), 10(-9) M) induced non-competitive inhibition of the concentration-response curve to 5-HT. The antagonist of 5-HT3 receptors 3-trophanyl-3,5-dichlorobenzoate (10(-7), 10(-5) M) did not inhibit the contractile curve to 5-HT. 4. These results suggest that 5-HT contracts the goat middle cerebral artery by acting mainly on 5-HT2 receptors.

摘要

在分离的山羊大脑中动脉节段中，5-羟色胺（5-HT，10⁻⁸ - 3×10⁻⁵ M）引起浓度依赖性收缩，EC50 = 2.1（1.9 - 2.5）×10⁻⁷ M，Emax = 50 mM氯化钾诱导收缩的64±2%。2. 使用了几种5-HT受体激动剂：（a）5-HT2受体激动剂α-甲基-5-羟色胺（10⁻⁷ - 3×10⁻⁴ M）诱导强烈收缩（51±6%）；（b）5-HT1受体选择性激动剂舒马曲坦（10⁻⁸ - 10⁻⁵ M）和5-羧基色胺（10⁻⁹ - 10⁻⁴ M）以及5-HT1A受体激动剂8-羟基-2-（二正丙基氨基）四氢萘（10⁻⁷ - 3×10⁻⁵ M）诱导微弱收缩（分别为8%、18%和14%）；（c）5HT3受体激动剂2-甲基-5-羟色胺（3×10⁻⁶ - 10⁻⁴ M）诱导几乎可忽略不计的收缩。3. 用5-HT1A和5-HT1B受体拮抗剂氰吲哚洛尔（10⁻⁸，10⁻⁶ M）、5-HT1/5-HT2受体拮抗剂麦角新碱（10⁻¹¹，10⁻⁹ M）和5-HT2受体拮抗剂酮色林（10⁻¹¹，10⁻⁹ M）预处理，对5-HT的浓度-反应曲线诱导非竞争性抑制。5-HT3受体拮抗剂3-托烷醇-3,5-二氯苯甲酸酯（10⁻⁷，10⁻⁵ M）不抑制对5-HT的收缩曲线。4. 这些结果表明，5-HT主要通过作用于5-HT2受体使山羊大脑中动脉收缩。