A calcium requirement for electric field-induced cell shape changes and preferential orientation.

Area of Science:

• Cell Biology
• Biophysics
• Electrophysiology

Background:

• Cells exhibit complex responses to external stimuli.
• Electric fields are increasingly recognized as modulators of cellular behavior.
• Calcium ions play a critical role in numerous cellular processes.

Purpose of the Study:

• To investigate the role of calcium in electric field-induced responses in C3H/10T1/2 mouse embryo fibroblasts.
• To elucidate the mechanisms by which electric fields affect cell morphology and survival.
• To identify potential calcium channels and pathways involved in these responses.

Main Methods:

• Exposure of fibroblasts to a steady electric field (10 V/cm).
• Manipulation of extracellular calcium concentrations and use of calcium channel blockers (lanthanum, D-600).
• Assessment of cell morphology, orientation, and viability using microscopy and pharmacological agents (A23187, W-13).

Main Results:

• Electric fields induced lamellar retraction and cell elongation, with orientation perpendicular to the field.
• Calcium depletion or blockade reduced field-induced responses.
• Elevated extracellular calcium enhanced responses, while ionophore A23187 altered cell shape without preferential orientation.
• Anticalmodulin drug W-13 inhibited responses, and calcium modulation affected cell death.

Conclusions:

• Electric field-induced cellular responses are critically dependent on calcium influx.
• Local calcium influx through field-opened channels likely activates the cytoskeletal network.
• Prolonged calcium influx may lead to cell death via necrotic calcification, highlighting calcium's dual role.