抄録
Too much increase of the plasma membrane permeability causes necrotic death in the many types of cells. Detail mechanisms of this type of cell death are still unclear. We use amphotericin B (amB) as the membrane pore formation agent and investigate the ionic dependency on the cell death caused by amB. First we apply propidium iodede (PI) to the HeLa cells together with 10 μg/ml amB and observe the staining nucleus by PI using the fluoresent microscope. 2 hours after apllication of amB, we could observe the PI signal in the nucleus, indicating that the large pores were formed after the application of amB. These pores should be larger than the pores formed by amB because PI did not enter into the cells just after amB application. Cl− replacement by gluconate or Cl− channel blocker, DIDS (0.5 mM) inhibited the staining of nulueus after amB application. Next we stained the lysosomes in the HeLa cells by FL-labelled pepstatin A. In the control condition, fluorescent dots were observed around the nucleus and such dots gradually disappered after amB application. Low Cl− condition or DIDS application inhibited the disappearance of the fluorescent dots by amB. These results suggest that the Cl− ions can enter into the cell after amB application and those ions may couse the disruption of lysosome, which enhances the membrane permeability increase by the attacking membrane proteins by the lysosomal enzymes. [J Physiol Sci. 2006;56 Suppl:S69]
