Intracellular pH in individual pituitary cells: measurement with a dual emission pH indicator.
Intracellular pH (pHi) can now be measured at the single cell level using dual emission wavelength microspectrofluorimetry with the fluorescent pH indicator SNARF 1 and its membrane permeant acetoxymethyl ester (SNARF 1/AM). We measured pHi of individual pituitary cells under both basal and stimulated conditions. The emitted fluorescence of SNARF 1 probe was calibrated following experimental manipulations of pHi in two types of rat pituitary cells. The calibration curves obtained in the two cell types were identical. We observed a Gaussian distribution of individual pHi with a wide dispersion (6.95 to 8) in the two cell populations. TRH (10(-7) M) and ionomycin (5 microM) induced a transient acidification followed by a sustained alkalinization, whereas K+ (50 mM) depolarization only exerted a transient acidification. These results show that the dual emission pH indicator SNARF 1 can be used to reliably investigate changes in pHi in individual endocrine cells.
Mariot
P
P
Laboratoire de Neurophysiologie, URA CNRS 1200, Université de Bordeaux II, France.
Sartor
P
P
Audin
J
J
Dufy
B
B
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002138:Calibration; D013006:Growth Hormone / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007424:Intracellular Fluid / Q000378:metabolism*; D015759:Ionomycin / Q000494:pharmacology; D007700:Kinetics; D010902:Pituitary Gland / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology; D011388:Prolactin / Q000378:metabolism; D051381:Rats; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology
D007202:Indicators and Reagents; D015759:Ionomycin; D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin; D013006:Growth Hormone; D011188:Potassium; D002118:Calcium