Subsequent to the discovery that the (+)-benzomorphan sigma receptor ligands, (+)-pentazocine and (+)-N-allylnormetazocine, stimulated tyrosine hydroxylase activity and dopamine synthesis in rat striatum in vitro, we reported a similar effect on a structurally similar series of 1-phenyl-3-aminotetrahydronaphthalenes (phenylaminotetralins, PAT's). Both racemic 1-phenyl-3-dimethylamino-6-chloro-7-hydroxytetralin (CI,OH-PAT) and racemic 1-phenyl-3-dimethylaminotetralin (H2-PAT) stimulated tyrosine hydroxylase with an EC50 of approximately 0.1 μM. The former was also found to have a non-specific dopamine releasing effect while the latter was devoid of such activity affording it the less complicated pharmacological profile of the two analogs. We previously reported the synthesis of tritium labeled Cl,OH-PAT to be used in radioreceptor and autoradiography studies and found that it labeled a sigma-like site in guinea pig brain with an apparent Kd of ∼50 pM and with a pharmacological profile unique from other known CNS receptors. Here we report the synthesis of high specific activity tritium labeled trans-(1R,3S)-(−)-H2-PAT as this enantiomer was found to be more active in the tyrosine hydroxylase assay and possessed approximately 45 fold greater affinity for the novel neuromodulatory sigma-like receptor.
继发现 (+)-benzomorphan sigma 受体
配体 (+)-pentazocine 和 (+)-N-allylnormetazocine 可刺激体外大鼠纹状体中
酪氨酸羟化酶的活性和
多巴胺的合成之后,我们又报道了结构相似的 1-苯基-3-
氨基四氢
萘系列(
苯胺四氢
萘,PAT's)也有类似的作用。外消旋 1-苯基-3-
二甲氨基-6-
氯-7-羟基四氢
萘素(CI,OH-PAT)和外消旋 1-苯基-3-
二甲氨基四氢
萘素(H2-PAT)都能刺激
酪氨酸羟化酶,
EC50 约为 0.1 μM。研究还发现,前者具有非特异性
多巴胺释放作用,而后者则不具有这种活性,因此在这两种类似物中,前者的药理特征并不复杂。我们曾报道过合成氚标记的 Cl,OH-PAT,并将其用于放射受体和自显影研究,结果发现它标记了豚鼠大脑中的一个类似σ的位点,表观 Kd 为 50 pM,其药理特征与其他已知的中枢神经系统受体不同。在此,我们报告了高特异活性氚标记反式-(1R,3S)-(-)-H2-PAT 的合成情况,因为我们发现这种对映体在
酪氨酸羟化酶试验中更有活性,而且对新型神经调节σ样受体的亲和力高出约 45 倍。