Non-basic D2 Receptor Binding Substances from Platns

在初步研究中，中药材Corydaus块茎的乙醇提取物的中性部分含有多巴胺D2受体结合物质。然而，详细的研究表明，活性成分实际上不是中性的，而是弱碱性的酚类生物碱，如异柯卡帕明。TIDS通过化学和药理相结合的方法，进一步检测了其他民间药用植物中是否存在与中枢神经受体D1、D2和5-Hl‘(5-羟色胺)1a、1b、1c具有结合活性的物质。与5-HT1a受体结合。活性成分鉴定为四氢阿尔斯通碱、β-育利宾碱和育芬宾碱。然而，这三种内分泌生物碱对肾上腺素能α2受体具有较强的结合活性，因此不具有选择性。从印度药用植物中分离得到选择性DL受体结合物质异冰片碱、雷尼汀和新生物碱2-羟甲基-10，11-亚甲基二氧基去甲吗啡，以及非选择性的DL/5-HT1a结合物质Boldine。内源性多巴胺和5-羟色胺是一些精神疾病的关键化合物。因此，上述生物碱可作为新型抗精神病药物的先导化合物。

In a preliminary study, the neutral fraction of the reethanol extract of the chinese trditional medicine CorydaUs tuber was shown to contain dopamine D2 receptor binding substances. Detailed studies revealed, however, the active principles were in fact not neutral, but weakly basic phenolic alkaloids such as isocorypalmine. Tids led us to examine further the presence of substances having binding activity to the central neuroreceptors Dl, D2 and 5-Hl'(5hydroxyttyptamine)la, lb, lc in other folk medicinal plants, by means of combination of chemical and pharmacological methods.Binding assays demonstrated that Anisonia elliptica contained substances. binding to the 5-HTla receptor. The active principles were identified as tetrahydroalstonine, beta-yoliimbine and yolfimbine. These three endole alkaloids had, however, stronger binding activity for tlie adrenergic alpha2 receptor and therefore, were not selective. From the imdian medicinal plant Lytsea glutinosa were isolated as selective Dl receptor binding substances isoboldine, reticuline, and a new alkaloid 2-hydroxylmethoy-10, 11-methlenedioxynoraporphine, together with nonselective Dl/5-HTla binding substance boldine.Endogeneous dopamine and 5-hydroxytryptandne are known as key compounds for some mental diseases. The above alkaloids can therefore be useful lead compounds for new antipsychotic drugs.