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Updated: Jul 28, 2026
07:26
Cell-based Calcium Assay for Medium to High Throughput Screening of TRP Channel Functions using FlexStation 3
Published on: August 17, 2011
Store-operated Ca2+-channels are sensitive to changes in extracellular pH
G Laskay1, K Kálmán, E Van Kerkhove
1Department of Botany, University of Szeged, Hungary. glaskay@bio.u-szeged.hu
Biochemical and Biophysical Research Communications
|October 4, 2005
Summary
Extracellular pH significantly impacts store-operated calcium entry in human neuroblastoma cells. Changes in external pH modulate calcium influx, suggesting a role in regulating cellular activity.
Area of Science:
- Neuroscience
- Cell Biology
- Physiology
Background:
- Store-operated calcium (Ca2+) entry is crucial for cellular signaling.
- The influence of extracellular pH on this process in human neuroblastoma cells remains incompletely understood.
Purpose of the Study:
- To investigate the sensitivity of store-operated Ca2+-entry to extracellular pH (pHo) and intracellular pH (pHi) in SH-SY5Y cells.
- To determine if pH changes modulate Ca2+ influx mediated by carbachol (CCH) or thapsigargin (TG).
Main Methods:
- SH-SY5Y human neuroblastoma cells were used.
- Intracellular Ca2+ stores were depleted using CCH or thapsigargin (TG).
- Extracellular pH was altered, and Mn2+-quenching experiments assessed Ca2+ entry rates.
Main Results:
- Extracellular acidification (lower pHo) suppressed CCH- and TG-mediated Ca2+ entry.
- Extracellular alkalinization (higher pHo) augmented both CCH- and TG-induced Ca2+ influx.
- Altered pHo did not significantly affect pHi, and changes in pHi did not impact CCH-induced Ca2+ entry.
Conclusions:
- Physiologically relevant changes in extracellular pH modulate store-operated Ca2+-entry in SH-SY5Y cells.
- These findings suggest that endogenous shifts in extracellular pH may regulate cell activity by influencing store-operated Ca2+-entry.
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