@article{APS4012,
author = {Tong-fei Wang and Chen Zhou and Ai-hui Tang and Shi-qiang Wang and Zhen Chai},
title = {Cellular mechanism for spontaneous calcium oscillations in astrocytes},
journal = {Acta Pharmacologica Sinica},
volume = {27},
number = {7},
year = {2016},
keywords = {},
abstract = {Aim: To determine the Ca2+ source and cellular mechanisms of spontaneous Ca2+ oscillations in hippocampal astrocytes.
Methods: The cultured cells were loaded with Fluo-4 AM, the indicator of intracellular Ca2+, and the dynamic Ca2+ transients were visualized with confocal laser-scanning microscopy.
Results: The spontaneous Ca2+ oscillations in astrocytes were observed first in co-cultured hippocampal neurons and astrocytes. These oscillations were not affected by tetrodotoxin (TTX) treatment and kept up in purity cultured astrocytes. The spontaneous Ca2+ oscillations were not impacted after blocking the voltage-gated Ca2+ channels or ethylenediamine tetraacetic acid (EDTA) bathing, indicating that intracellular Ca2+ elevation was not the result of extracellular Ca2+ influx. Furthermore, the correlation between the spontaneous Ca2+ oscillations and the Ca2+ store in endoplasmic reticulum (ER) were investigated with pharmacological experiments. The oscillations were: 1) enhanced when cells were exposed to both low Na+ (70 mmol/L) and high Ca2+ (5 mmol/L) solution, and eliminated completely by 2 μmol/L thapsigargin, a blocker of sarcoplasmic reticulum Ca2+-ATPase; and 2) still robust after the application with either 50 mol/L ryanodine or 400 μmol/L tetracaine, two specific antagonists of ryanodine receptors, but depressed in a dose-dependent manner by 2-APB, an InsP3 receptors (InsP3R) blocker.
Conclusion: InsP3R-induced ER Ca2+ release is an important cellular mechanism for the initiation of spontaneous Ca2+ oscillation in hippocampal astrocytes.},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/4012}
}