水蛭（医用水蛭）中中枢和外周5-羟色胺受体的重新定义。

Central and peripheral 5-HT receptors in the leech (Hirudo medicinalis) redefined.

Leake L D, Koubanakis M

School of Biological Sciences, University of Portsmouth, Hants, UK.

Gen Pharmacol. 1995 Dec;26(8):1709-17. doi: 10.1016/0306-3623(95)00065-8.

Abstract

5-Hydroxytryptamine (5-HT) receptors in the Retzius neurones (R cells) and longitudinal body wall muscle strips of the leech H. medicinalis were studied using a range of selective agonists developed for mammalian receptors. 2. All agonists induced hyperpolarisation of R cells: the order of their potency was 5-HT > 5-CT > 2-Me 5HT > alpha-Me-5-HT > > CGS-12066B = 5MeOT > PAPP > Buspirone. This receptor is most like a mammalian 5-HT1C/2 receptor. 3. 5-HT induces relaxation of body wall strips, preceded at higher doses by contraction or an increase in spontaneous contractions. The relaxing effect was best mimicked by 5-CT and alpha-Me-5-HT, suggesting a 5-HT1C/2 receptor. The contractile effect was best mimicked by 5-MeOT suggesting a 5-HT4-like receptor. The overall potency of agonists on the body wall muscle was 5-MeOT > 5-CT > 5-HT > alpha-Me-5-HT > 2-Me 5-HT > PAPP > Buspirone > > CGS-12066B. 4. Results suggest that either the sites of 5-HT action possess several different receptors or the receptors themselves are more complex with multiple properties.

摘要

使用为哺乳动物受体开发的一系列选择性激动剂，研究了药用蛭的雷丘斯神经元（R细胞）和体壁纵肌条中的5-羟色胺（5-HT）受体。2. 所有激动剂均诱导R细胞超极化：其效力顺序为5-HT > 5-CT > 2-甲基5-HT > α-甲基-5-HT > > CGS-12066B = 5-甲氧基色胺 > PAPP > 丁螺环酮。该受体最类似于哺乳动物的5-HT1C/2受体。3. 5-HT诱导体壁条松弛，高剂量时先出现收缩或自发收缩增加。5-CT和α-甲基-5-HT最能模拟这种松弛作用，提示为5-HT1C/2受体。5-甲氧基色胺最能模拟收缩作用，提示为5-HT4样受体。激动剂对体壁肌肉的总体效力为5-甲氧基色胺 > 5-CT > 5-HT > α-甲基-5-HT > 2-甲基5-HT > PAPP > 丁螺环酮 > > CGS-12066B。4. 结果表明，要么5-HT作用位点具有几种不同的受体，要么受体本身更复杂，具有多种特性。