Effects of Polyphenols from Green Tea Extracts on Bovine Chromaffin Cells

綠茶之多酚萃取物對嗜鉻細胞鈣離子電流之影響

謝瑞頤(Jui-Yi Hsieh) ； 潘建源(Chien-Yuan Pan)

《Acta Zoologica Taiwanica》 14卷2期 (2004/10) Pp. 157-158

https://doi.org/10.6576/AZT.2004.14.(2).34

摘要

綠茶成分中，含有相當大之比例爲多酚化合物(polyphenols)，儘管已經有相當多之研究投入其性質的探討，對其作用於細胞的機制仍然不清楚。在此報告中，我們以perforated whole cell patch的電生理方式，探討多酚化合物之一，ECG，對嗜鉻細胞(chromaffin cells)鈣離子電流的影響。胞內鈣離子濃度關係著許多的生理活動，包括進行胞吐作用(exocytosis)以釋放出腎上腺素(epinephrine)及正腎上腺素(norepinephrin)。我們欲從了解其作用的機制和路徑，來了解多酚化合物在生理上之影響。實驗中我們發現，多酚化合物，ECG，主要透過增強L及P/Q type之鈣離子通道(calcium channel)來達成其作用，且不受到PKC抑制物Calphostin C及tyrosine kinase抑制物Genistein之影響，表示此機制應獨立於這兩種分子所媒介的路徑，至於ECG確切的作用機制及方式，則需要更進一步的研究。

關鍵字

綠茶 ； 多酚化合物 ； 嗜鉻細胞 ； perforated whole cell patch ； 鈣離子通道

並列摘要

Polyphenols are one of the major constituents in green tea extracts. Although intensive researches have already performed on this issue, the mechanism of how polyphenols affect cell physiology remains unclear. In this report, we used electrophysiological technique, perforated whole cell patch clamp, to examine the effects of ECG, one of the major polyphenols in green tea extracts, on calcium currents in bovine chromaffin cells. As many researches showed, calcium ions play an important role in varies aspects of cell physiology, including exocytosis and endocytosis. Our data showed that ECG could enhance L and P/Q type calcium channel currents. In addition, this effect was insensitive to PKC inhibitor, Calphostin C, and general tyrosine kinase, genistein. However, the details of how ECG enhances calcium currents may need more researches to clarify.

並列關鍵字

green tea ； Polyphenols ； chromaffin cells ； perforated whole cell patch ； calcium channel