Related Experiment Videos
Studies on human porin XXII: cell membrane integrated human porin channels are involved in regulatory volume decrease
F P Thinnes1, K P Hellmann, T Hellmann
1Abteilung Immunchemie, Max-Planck-Institut für experimentelle Medizin, Göttingen, Germany.
Molecular Genetics and Metabolism
|June 28, 2000
Summary
Cell volume regulation is crucial for cell function. Blocking porin channels with antibodies prevents regulatory volume decrease (RVD) in HeLa cells, demonstrating porin
Area of Science:
- Cell Biology
- Physiology
- Molecular Biology
Background:
- Cell volume regulation, including regulatory volume decrease (RVD), is vital for cell survival and function under osmotic stress.
- Volume-sensitive chloride/anion channels are central to RVD, and their inhibition abolishes this process.
- Previous evidence suggests eukaryotic porins integrated into the plasma membrane function as these critical chloride/anion channels involved in cell volume regulation.
Purpose of the Study:
- To investigate the role of porin in cell volume regulation, specifically in the context of regulatory volume decrease (RVD).
- To demonstrate that porin functions as a volume-sensitive chloride/anion channel.
- To validate the use of monoclonal anti-porin antibodies as a tool in physiological studies of cell volume regulation.
Main Methods:
- Utilized HeLa cells subjected to hypotonic stress (70 mM NaCl Ringer solution).
- Employed monoclonal mouse anti-human type-1 porin antibodies to block porin channels.
- Used video camera monitoring for real-time, noninvasive observation of cell size changes over time.
- Compared the effects of anti-porin antibodies with the established anion channel inhibitor DIDS.
Main Results:
- HeLa cells pre-incubated with anti-porin antibodies showed a significant volume increase (70%) after hypotonic stimulus.
- These cells failed to return to their original volume, indicating abolished RVD.
- The anion channel inhibitor DIDS produced similar effects, corroborating the role of anion channels in RVD.
Conclusions:
- Monoclonal anti-porin antibodies effectively block porin function, confirming porin's involvement in regulatory volume decrease (RVD).
- Porin channels are essential components of the volume-sensitive chloride/anion channel pathway mediating RVD.
- Anti-porin antibodies serve as a valuable and suitable tool for physiological investigations into cell volume regulation.