增加雄果蠅大腦內特定多巴胺神經元之多巴胺合成可提高老齡化雄果蠅之性活動力與性衝動

Increased dopamine synthesis in specific dopaminergic neurons reverse age-related declines in sexual activity and sex drive in male Drosophila

溫榮崑(Rong-Kun Wen)

指導教授 ： 傅在峰

國立暨南國際大學/科技學院/應用化學系/碩士(2012年)

摘要

在各項的臨床醫學研究中證實，動物體會隨著老化(aging)現象改變其行為反應與認知能力；其中，性活動力(sexual activity)與性衝動(sex drive)隨著老化而降低的現象，也在各項研究中被發現。但是，對於此現象所涉及的分子機制至今尚未被釐清。果蠅求偶行為的分析與量化已被清楚的確立；同時，在遺傳學上他可以提供適切的遺傳分析工具與大規模研究的優勢，因此，本論文將以果蠅為模式動物，進行老化與性活動之間關係的研究。多巴胺(dopamine)已證實參與調控哺乳類動物的性行為與性慾，本論文發現，隨著雄性果蠅的老齡化，性活動力與性衝動皆顯著下降，有趣的是，透過多巴胺的補充可回復此一現象。透過分析果蠅大腦中不同的多巴胺神經元，我們證實一群將神經纖維伸入蕈狀體calyx與lateral horn的PPL2ab神經元，當其多巴胺含量增加時，即可逆轉老齡化果蠅之性活動力與性衝動低下現象。對於調控雄果蠅大腦中少數多巴胺神經元之多巴胺含量，得以回復因老化所造成的性活動低下現象，預期此結果可為針對調節性活動力與性衝動相關分子機制研究，提供一個嶄新的研究分析平台。

關鍵字

果蠅 ； 求偶行為 ； 多巴胺 ； 老化 ； 性活動力 ； 性衝動

並列摘要

The declination of sexual activity and sexual drive along with age has been proven in various clinical studies. The involved cellular and molecular mechanisms have not been clarified. Drosophila provides an appropriate genetic analytical tool and the research advantage of large-scale analyses that the analyses and quantification of courtship behavior have been clearly confirmed. Dopamine has been proven to participate in control of the sexual desire in mammals. In this study, increasing dopamine amount in dopaminergic neurons, the declination of courting activity and sexual drive of Drosophila along with ageing could be slowed down. Interestingly, we demonstrate the existence of critical circuit in PPL2ab neurons which innervate the calyx of mushroom bodies (MBs) and lateral horn through DA enhance the male sexual activity and sex drive. As such a complicated behavior could be simply controlled by this neural circuitry, the outcome may become an effective platform for relevant research on sexual activity.

並列關鍵字

Drosophila ； courtship ； dopamine ； aging ； sexual activity ； sex drive

參考文獻

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