Portolés M T, Ainaga M J, Municio A M, Pagani R
Department of Biochemistry and Molecular Biology I, Faculty of Chemistry, Universidad Complutense, Madrid, Spain.
Biochim Biophys Acta. 1991 Mar 19;1092(1):1-6. doi: 10.1016/0167-4889(91)90170-3.
In this study, the fluorescent Ca2+ probe fura-2 and the fluorescent pH indicator BCECF have been used to monitor cytosolic free Ca2+ and intracellular pH (pHi), respectively, in isolated and cultured hepatocytes treated with Escherichia coli O111:B4 endotoxin. Uptake of 45Ca2+ was also measured to study the effect of endotoxin on the extracellular calcium influx. Endotoxin treatment produced a progressive increase of cytosolic Ca2+ in a dose-dependent manner caused by both induction of a significant release of Ca2+ from intracellular stores and stimulation of the extracellular calcium influx. The perturbation of Ca2+ homeostasis by endotoxin may cause an abnormal stimulation of physiological processes, developing lethal cell injury. Endotoxin also produced a significant decrease in the pHi of hepatocytes which can justify important metabolic alterations during endotoxicosis.
在本研究中，荧光Ca2+探针fura-2和荧光pH指示剂BCECF分别用于监测经大肠杆菌O111:B4内毒素处理的分离培养肝细胞中的胞质游离Ca2+和细胞内pH（pHi）。还测量了45Ca2+的摄取，以研究内毒素对细胞外钙内流的影响。内毒素处理导致胞质Ca2+呈剂量依赖性逐渐增加，这是由细胞内钙库中Ca2+的大量释放以及细胞外钙内流的刺激共同引起的。内毒素对Ca2+稳态的干扰可能会异常刺激生理过程，导致致命的细胞损伤。内毒素还导致肝细胞的pHi显著降低，这可以解释内毒素血症期间重要的代谢改变。
