Maura G, Raiteri M
Eur J Pharmacol. 1986 Oct 7;129(3):333-7. doi: 10.1016/0014-2999(86)90443-7.
The effects of 5-hydroxytryptamine (5-HT) on the release of [3H]acetylcholine ([3H]ACh) from rat hippocampal nerve endings were investigated using synaptosomes labelled with [3H]choline and depolarized in superfusion with 15 mM KCl. The release of [3H]ACh was concentration dependently inhibited by exogenous 5-HT. The concentration-response curve of 5-HT was shifted to the right in a parallel way by methiothepin. The 5-HT2 antagonists ketanserin or methysergide did not antagonize the effect of 5-HT. The 5-HT1 agonist 5-methoxy-3-[1,2,3,6-tetrahydropyridin-4-yl]-1H-indole (RU 24969) mimicked 5-HT, whereas the 5-HT1A selective agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) was ineffective. When used as a 5-HT1A/5-HT1B antagonist, (-)propranolol antagonized 5-HT whereas spiperone (a 5-HT1A displacer) did not. The 5-HT1C selective antagonist mesulergine was also ineffective towards 5-HT. It can be concluded that hippocampal cholinergic terminals are endowed with inhibitory 5-HT receptors which appear to belong to the 5-HT1B subtype.
利用用[³H]胆碱标记并在含15 mM氯化钾的灌注液中去极化的突触体，研究了5-羟色胺（5-HT）对大鼠海马神经末梢释放[³H]乙酰胆碱（[³H]ACh）的影响。外源性5-HT对[³H]ACh的释放有浓度依赖性抑制作用。美噻吨使5-HT的浓度-反应曲线平行右移。5-HT₂拮抗剂酮色林或甲基麦角新碱不能拮抗5-HT的作用。5-HT₁激动剂5-甲氧基-3-[1,2,3,6-四氢吡啶-4-基]-1H-吲哚（RU 24969）模拟5-HT的作用，而5-HT₁A选择性激动剂8-羟基-2-（二正丙基氨基）四氢萘（8-OH-DPAT）则无效。当用作5-HT₁A/5-HT₁B拮抗剂时，（-）普萘洛尔能拮抗5-HT，而螺哌隆（一种5-HT₁A置换剂）则不能。5-HT₁C选择性拮抗剂美舒麦角对5-HT也无效。可以得出结论，海马胆碱能终末具有抑制性5-HT受体，这些受体似乎属于5-HT₁B亚型。
