Schlicker E, Fink K, Zentner J, Göthert M
Institut für Pharmakologie und Toxikologie, Universität Bonn, Germany.
Naunyn Schmiedebergs Arch Pharmacol. 1996 Aug-Sep;354(3):393-6. doi: 10.1007/BF00171075.
Hippocampal slices were prepared from brain tissue of patients undergoing neurosurgery for epilepsy. The slices were incubated with 3H-serotonin (3H-5-HT) and then superfused with physiological salt solution containing 6-nitroquipazine. Tritium overflow was evoked either electrically (3 Hz) or by K+ 25 mM. The electrically evoked overflow of tritium was almost abolished by tetrodotoxin or by omission of Ca2+ ions. 5-HT 0.1 and 1 microM reduced the evoked overflow by 38 and 55%, respectively. The effect of 5-HT 1 microM was abolished by the 5-HT1/2 receptor antagonist methiothepin 1 microM, which, by itself, increased the evoked overflow by 59%. Tritium overflow evoked by high K+ in slices superfused with medium containing tetrodotoxin was reduced by 5-HT 1 microM by 49%. This effect was markedly attenuated by methiothepin 0.32 microM, which, by itself, tended to increase the evoked overflow. The results show that the serotoninergic neurones of the human hippocampus are endowed with presynaptic inhibitory autoreceptors.
从因癫痫接受神经外科手术患者的脑组织中制备海马切片。将切片与³H - 血清素（³H - 5 - HT）一起孵育，然后用含有6 - 硝基喹哌嗪的生理盐溶液进行灌流。通过电刺激（3Hz）或25mM的K⁺诱发氚溢出。电诱发的氚溢出几乎被河豚毒素或去除Ca²⁺离子所消除。0.1和1μM的5 - HT分别使诱发的溢出减少38%和55%。1μM的5 - HT的作用被1μM的5 - HT₁/₂受体拮抗剂美噻吨所消除，而美噻吨本身使诱发的溢出增加59%。在含有河豚毒素的培养基灌流的切片中，高K⁺诱发的氚溢出被1μM的5 - HT减少了49%。0.32μM的美噻吨显著减弱了这种作用，而美噻吨本身倾向于增加诱发的溢出。结果表明，人类海马的5 - 羟色胺能神经元具有突触前抑制性自身受体。
