Direct measurements of membrane potential and membrane resistance of human red cells

Abstract

1. In order to evaluate the membrane potentials calculated from the distribution of chloride ions in human red cells and plasma, it is desirable to have a direct measurement of the transmembrane potential of these cells. 2. A method has been devised for introducing a capillary micro‐electrode into human red cells. The method allows simultaneous measurements of potential and membrane resistance with only one micro‐electrode located in the cell. 3. Upon impalement of single cells in plasma, a scatter of membrane potentials and of resistance values was obtained. The potential drop never exceeded ‐14 mV and the maximum resistances were about 7 Ω. cm2. Positive potentials were obtained on impalement of red cell aggregates. 4. Arguments are given to support the view that it is in these cells which suffer least damage from the impalement that maximum values of membrane potentials and resistances are observed. The errors caused by the change in the liquid junction during the impalement have been estimated. 5. As judged from this study, it seems permissible under normal conditions to calculate the membrane potential of the red cell from the chloride concentrations in plasma and in intracellular water.

Ouabain-insensitive salt and water movements in duck red cells. III. The role of chloride in the volume response.

“…There is now good evidence that this is reasonable for nucleated red cells (Lassen, 1972). Even if it is not correct in detail, it is unlikely that the discrepancy would be very great.…”

Mitochondrial Membrane Potential: Evidence from Studies with a Fluorescent Probe

“…However, in at least some other studies [e.g., Sekiya's (8) and Johnstone's (9) ] the K+-sensitive membrane potential decayed considerably more slowly (with a half-time of 10 sec in Sekiya's work). Consequently, the results of Lassen (14) and [4][5][6][7][8][9][10][11][12][13] 1cm2 (15) (14). Several other workers estimate much larger potentials in actively metabolizing mitochondria.…”

“…They proposed that a similar perhaps faster decay took place in our experiments. However, in at least some other studies [e.g., Sekiya's (8) (14) and [4][5][6][7][8][9][10][11][12][13] 1cm2 (15) have been recorded from the excitable face and 0.1-0.4 flCm2 (15) for the nonexcitable face.A number of studies have attempted to estimate the mitochondrial membrane potential by indirect means. Harris and Pressman (5) have calculated membrane potentials in rat liver mitochondria from anion distributions.…”

A piezoelectric device to aid penetration of small nerve fibers with microelectrodes

“…Various means of facilitating cell penetration have already been reported: (1) manual tapping of the experimental set-up (Tyler and Monroy, 1955); (2) electromagnetic jolting of the preparation (Tomita, 1965), (3) electromagnetic tapping of the microelectrode (Frank and Becker, 1964;van der Pers, 1980;Hamdorf personal communication); (4) magnetostrictive tapping of the microelectrode (Weiler and Zettler, 1976); (5) electrostrictive tapping of the microelectrode (Pascoe, 1955;Ellis, 1962;Lassen and Sten-Knudsen, 1968;Rikmenspoel and Lindemann, 1971;Chen, 1978;Fromm et al, 1980); (6) DC impulse through microelectrode (Zettler and Järvilehto, 1971); (7) high frequency current through microelectrode (DeVoe, 1975), (8) electrostrictive vibration of microelectrode (Ellis, 1962;Chowdhury, 1969).…”