应用流式细胞技术(FCM)及PI/FDA染色方法,在不同Cu^2+浓度处理后,从细胞膜完整性、脂酶活性两方面同时研究了Cu^2+处理对微囊藻细胞的急性毒性作用.检测结果表明,在不同浓度Cu^2+处理M.aeruginousa 1h时,PI荧光检测显示藻细胞膜的完整性几乎没有受到影响,而FDA荧光检测则表明藻细胞的脂酶活性在一定浓度受到刺激.在Cu^2+处理24h时,随着Cu^2+浓度的增高,PI和FDA荧光强度变化的概率均呈明显的浓度抑制型变化,说明在此时Cu^2+作用下FDA荧光的下降,不仅与细胞内脂酶活性受到抑制有关,而且也是高浓度Cu^2+作用下细胞膜受损而导致细胞内含物外流的结果.
The acute effects of copper on the membrane integrality and esterase activity of Microcystis aeruginosa were investigated using flow cytometry ( FCM ) and FDA/PI staining. After 1 h copper exposure, there was no significant effect on the membrane integrality in all concentration treatments, while modest stimulation of esterase activity was detectable by FDA staining. After 24 h copper exposure, this stimulation disappeared. In contrast, FDA fluorescence decreased as the copper concentration increased. At same time, the membrane was destructed detected by PI staining. The results suggested that the changes in FDA fluorescence were also related to the amount of fluorescein that leaked out from the cells. So the decreased FDA fluorescence was due to both inhibition of intracellular esterases and consequence of changes in membrane permeability.