Dopaminergic neurons of the midbrain are the main source of dopamine (DA) in the mammalian central nervous system. As a neurotransmitter DA were released by dopaminergic neurons to activate or modulate downstream neuron. DA circuits in brain which composed by lots dopaminergic neurons involved in many psychological and physiological functions of brain such as cognition, reward prediction, sense of pleasure and voluntary movement. On the other way, dysfunction of dopaminergic neurons may result in several neurodegenerative disorders like Parkinson’s disease. Previous studies suggested that lose of dopaminergic neurons in the substantia nigra is responsible for dysfunction in movement in patients of Parkinson’s disease. We had developed an DA sensor and showed the sensor can detect dopamine in vitro. In this thesis we expressed the probe on mammal cell membrane to determine its activity and level of sensitivity upon DA treatment. Through this work such kind of probe may be expressed in neuron and observe the activation of DA circuits when applying different stimulations.

多巴胺是神經系統中一類重要的神經傳導物質，多巴胺生成細胞藉由釋放多巴胺來傳遞神經訊號或調節下游的神經細胞。在神經系統中多個多巴胺生成細胞共同組成多巴胺迴路，調節多類神經在生理和心理上的作用諸如辨識物體、預期獎勵、產生愉悅感、自主性運動…等等。此外，神經系統中的多巴胺生成細胞也和一些神經退化性疾病相關，像是帕金森氏症。大量的研究結果指出，在病人身上發生的多巴胺生成細胞的缺失，使大腦中調控肢體運動的部分無法接收到足夠的多巴胺刺激，因此出現帕金森氏症的相關病症。多巴胺在神經系統運作機轉中扮演如此重要角色，因此，許多研究團隊都致力於開發新的多巴胺偵測方式試圖在活體中觀測多巴胺和神經系統運作的相關性。我們利用基因工程的方式發展出多巴胺偵測探針，並證明此多巴胺偵測探針在多巴胺存在的情況下可偵測多巴胺存在。更進一步，我們將此多巴胺偵測探針表現在細胞膜外側，並測試此探針的作用能力。我們希望未來能將這探針用以觀測特定神經元運作時多巴胺釋放的作用及功能。並可進一步分析多巴胺調控與神經退化疾病之關連性。

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