Potentiometric measurement of cell volume changes and intracellular ion concentrations under voltage-clamp conditions in invertebrate nerve cells.
Because changes in cell volume might disturb the normal function of animal cells, most cells are endowed with volume-regulating mechanisms. Experimentally induced changes in cell volume are often paralleled by changes in the membrane potential, which might affect a variety of transport processes across the cell membrane and, in turn, volume regulation [1, 2]. We have shown previously that multi-barrelled ion-selective microelectrodes are useful tools for measurement of cell volume and the intracellular concentrations of ions that might be relevant to volume regulation [1]. To investigate whether voltage-dependent transport processes are involved in cell-volume regulation we combined the potentiometric technique of ion-selective microelectrodes with the voltage-clamp technique. This combination enables simultaneous recording of cell volume, relevant intracellular ion concentrations, and ion currents across the cell membrane at a fixed membrane potential.
Institut für Neurobiologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany. dierkes@uni-duesseldorf.de
Paul Wilhelm
PW
Dierkes
Philippe
P
Coulon
Susanne
S
Neumann
Wolf-Rüdiger
WR
Schlue
D000818:Animals; D007448:Invertebrates; D007477:Ions / Q000032:analysis*; D008839:Microelectrodes; D009474:Neurons / Q000737:chemistry*; D018408:Patch-Clamp Techniques; D011199:Potentiometry / Q000379:methods*
D007477:Ions