Cookies help us deliver our services. By using our services, you agree to our use of cookies. More information

Loupatatzis 2002 Cell Physiol Biochem

From Bioblast
Publications in the MiPMap
Loupatatzis C, Seitz G, Schoenfeld P, Lang F, Siemen D (2002) Single-channel currents of the permeability transition pore from the inner mitochondrial membrane of rat liver and of a human hepatoma cell line. Cell Physiol Biochem 12:269-78.

» PMID: 12438763

Loupatatzis C, Seitz G, Schoenfeld P, Lang F, Siemen D (2002) Cell Physiol Biochem

Abstract: Single-channel currents were recorded from inner mitochondrial membranes of HepG2 hepatoma cells and of normal rat liver cells by means of patch-clamp techniques. The current events showed variable amplitudes of up to 1.1 ± 0.2 nS (n = 35) at room temperature (24 °C) and of up to 1.5 ± 0.2 nS (n = 10) at 34 °C including large numbers of subconductance states. Voltages of -40 mV and below closed the channels usually with a delay of about 2 min. Increasing Ca2+ concentrations activated the channels, whereas cyclosporin A (100 nM) blocked. The concentration-response relation for the Ca2+-effect could be fitted best using an EC50 of 10 μM and a Hill coefficient of 1.5. Taken together the results indicate that we recorded from the permeability transition pore (PTP). As PTP activity may be related to apoptosis we tested if lysate from differently treated T-lymphocytes (Jurkat cells) was able to induce PTP activity in HepG2 cells. Lysate of untreated cells completely abolished the activity at a Ca2+ oncentration of 18 nM (buffered by EGTA), i.e. three orders of magnitude below the EC50. Under these conditions the lysate is not likely to contain stable factors that could open the PTP. Preliminary experiments show PTP activity in CD95-activated lysate.


O2k-Network Lab: DE Magdeburg Siemen D, DE Magdeburg Schoenfeld P


Labels:


Organism: Rat  Tissue;cell: Liver  Preparation: Isolated mitochondria 


Coupling state: LEAK, OXPHOS 

HRR: Oxygraph-2k