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Monitoring the Effect of Osmotic Stress on Secretory Vesicles and Exocytosis
Published on: February 19, 2018
[Water and ion balance in rat thymocytes under apoptosis induced with dexamethasone or etoposide. Ion-osmotic model
A A Vereninov1, E V Volgareva, V V Matveev
1Institute of Cytology, RAS, St. Petersburg. veren@mail.cytspb.rssi.ru
Tsitologiia
|October 3, 2003
Summary
Cell volume decrease during apoptosis is driven by ion and water loss. Apoptotic thymocytes show reduced intracellular potassium and increased sodium, supporting the ion-osmotic model of apoptotic volume decrease.
Area of Science:
- Cell Biology
- Biochemistry
- Physiology
Background:
- Apoptotic volume decrease (AVD) is a hallmark of apoptosis.
- The precise mechanisms regulating ion and water balance during AVD are not fully understood.
Purpose of the Study:
- To investigate the ion and water balance during apoptotic volume decrease (AVD) in rat thymocytes.
- To analyze the osmotic model of AVD using dexamethasone or etoposide treatments.
Main Methods:
- Cell buoyant density analysis using Percoll gradients to assess intracellular water.
- Flame emission analysis for intracellular potassium and sodium content.
- Flow cytometry and light microscopy to verify apoptosis and cell morphology changes.
Main Results:
- Dexamethasone or etoposide treatment induced apoptosis, characterized by increased cell buoyant density and decreased cell size.
- Apoptotic cells exhibited lower intracellular water content and reduced total potassium and sodium content.
- Apoptotic cells showed decreased intracellular potassium and increased intracellular sodium.
Conclusions:
- The ion-osmotic model adequately explains the cell volume decrease observed during apoptosis.
- Changes in intracellular ion concentrations (decreased K+, increased Na+) and associated anion loss contribute significantly to AVD.
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