AJP - Cell Physiology, Vol 253, Issue 1 C121-C125, Copyright © 1987 by American Physiological Society
Flow cytometric analysis of intracellular pH in 3T3 cells
R. J. Gillies, J. Cook, M. H. Fox and K. A. Giuliano
Techniques to determine intracellular pH generally report the average pH of
population and do not indicate whether or not there is significant variance
among cells within the population. Population variance is important to
ascribe pH changes on a per cell basis. The magnitude of the pH change in
individual cells is important to ascribe physiological function to changes
in pH. To determine the variability of cell responses, we have used dual
wavelength fluorescence emission spectroscopy of intracellular
dicyanohydroquinone monitored with flow cytometry to determine the pH of
normal and transformed 3T3 cells in response to serum or serum components.
All cells were mechanically harvested from subconfluent cultures. Large
differences in pH were observed between serum-deprived and
serum-conditioned normal, but not transformed, cells. Addition of serum
caused cytosolic alkalinization, with the serum-deprived cells responding
more slowly. Titration of cells with submaximal doses of serum indicate
that the response of pH is graded, that all cells respond in similar
manner, and that the relative affinity of transformed cells for the serum
components causing the pH effect is about twice that of normal cells.
