Loss of dopamine neurons is central to the manifestation of Parkinson’s disease motor symptoms. The dopamine precursor L-DOPA, the most commonly used therapeutic agent for Parkinson’s disease, can restore normal movement yet cause side-effects such as dyskinesias upon prolonged administration. Dopamine D1 and D2 receptors activate G-protein- and arrestin-dependent signaling pathways that regulate various dopamine-dependent functions including locomotion. Studies have shown that shifting the balance of dopamine receptor signaling toward the arrestin pathway can be beneficial for inducing normal movement, while reducing dyskinesias. However, simultaneous activation of both D1 and D2Rs is required for robust locomotor activity. Thus, it is desirable to develop ligands targeting both D1 and D2Rs and their functional selectivity. Here, we report structure–functional–selectivity relationship (SFSR) studies of novel apomorphine analogs to identify structural motifs responsible for biased activity at both D1 and D2Rs.

中文翻译：

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新型阿扑吗啡类似物的结构-功能-选择性关系研究，以开发D1R / D2R配体。

多巴胺神经元的丢失是帕金森氏病运动症状表现的关键。多巴胺前体L-DOPA是帕金森氏病最常用的治疗剂，长时间服用可恢复正常运动，但会引起诸如运动障碍等副作用。多巴胺D1和D2受体激活G蛋白和抑制蛋白依赖性信号传导途径，调节各种多巴胺依赖性功能，包括运动。研究表明，将多巴胺受体信号传递的平衡向抑制蛋白途径转移，可有利于诱导正常运动，同时减少运动障碍。然而，D1和D2Rs的同时激活是鲁棒运动活动所必需的。因此，期望开发靶向D1和D2R两者的配体及其功能选择性。这里，