Mariot P, Sartor P, Audin J, Dufy B
Laboratoire de Neurophysiologie, URA CNRS 1200, Université de Bordeaux II, France.
Life Sci. 1991;48(3):245-52. doi: 10.1016/0024-3205(91)90351-b.
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.
现在可以使用双发射波长显微荧光测定法，借助荧光pH指示剂SNARF 1及其膜渗透性乙酰氧基甲酯（SNARF 1/AM）在单细胞水平测量细胞内pH（pHi）。我们在基础条件和刺激条件下测量了单个垂体细胞的pHi。在两种类型的大鼠垂体细胞中，通过对pHi进行实验操作后，对SNARF 1探针发出的荧光进行了校准。在两种细胞类型中获得的校准曲线是相同的。我们观察到在两个细胞群体中，个体pHi呈高斯分布，且离散度较大（6.95至8）。促甲状腺激素释放激素（TRH，10⁻⁷ M）和离子霉素（5 μM）诱导了短暂的酸化，随后是持续的碱化，而50 mM K⁺去极化仅引起短暂的酸化。这些结果表明，双发射pH指示剂SNARF 1可用于可靠地研究单个内分泌细胞中pHi的变化。
