Related Experiment Video
Updated: Sep 9, 2025
07:17
Single-Cell Calcium Imaging for Studying the Activation of Calcium Ion Channels
Published on: December 13, 2024
901
Osmotic pressure-induced calcium response states
Zidan Gao1, Keiji Naruse2, Masatoshi Morimatsu2
1Department of Cardiovascular Physiology, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
FEBS Open Bio
|August 30, 2025
Summary
Cells respond to hypotonic stress with calcium signals originating from the endoplasmic reticulum. These signals propagate to neighboring cells, revealing a new mechanism for osmotic adaptation and intercellular communication.
Area of Science:
- Cellular biology
- Physiology
- Biochemistry
Background:
- Cellular homeostasis relies on osmotic pressure regulation.
- Mechanisms of cellular response to osmotic stress are not fully understood.
Purpose of the Study:
- Investigate cellular responses to acute osmotic stress.
- Identify signaling pathways involved in osmotic adaptation.
Main Methods:
- Applied rapid osmotic pressure stimulation to cultured HEK293T cells.
- Observed intracellular calcium dynamics.
- Utilized ryanodine receptor 2 and Connexin 43 inhibitors.
Main Results:
- Hypotonic stimulation induced distinct intracellular calcium patterns.
- Hypertonic and isotonic stress did not elicit similar calcium responses.
- Calcium signals originated from the endoplasmic reticulum and propagated via gap junctions.
Conclusions:
- Calcium signaling plays a crucial role in the acute cellular response to hypotonic stress.
- Ryanodine receptor 2 and Connexin 43 are key mediators of this response.
- Discovered a novel mechanism for intercellular communication during osmotic adaptation.
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