Visualization of cytosolic free calcium distribution and mobilization in guinea pig gastric chief cells.
Distribution and temporal change of free calcium concentration [( Ca2+]i) in single guinea pig gastric chief cells were visualized by a digital imaging microscope equipped with a microspectrofluorometer. The distribution was not homogeneous; a higher [Ca2+]i area was often localized in some restricted regions of the endoplasm and also at the peripheral cytoplasm just beneath the plasma membrane. When stimulated with cholecystokinin, [Ca2+]i increased transiently in the apical peripheral cytoplasm and in the endoplasmic regions. This Ca2+ mobilization which precedes the biphasic pepsinogen secretion was composed of a rapid Ca2+ release from the intracellular store(s) as well as a rapid and a more sustained Ca2+ entry from the extracellular space.
Tsunoda
Y
Y
Department of Physiology, Kansai Medical University, Osaka, Japan.
Yodozawa
S
S
Tashiro
Y
Y
D000818:Animals; D002118:Calcium / Q000032:analysis* / Q000378:metabolism; D003600:Cytosol / Q000032:analysis*; D005753:Gastric Mucosa / Q000032:analysis / Q000166:cytology* / Q000378:metabolism; D006168:Guinea Pigs; D008297:Male; D013050:Spectrometry, Fluorescence / Q000379:methods; D013053:Spectrophotometry / Q000379:methods
D002118:Calcium