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Updated: Aug 2, 2026
04:59
Spinal Cord Electrophysiology
Published on: January 19, 2010
Ca++ dependent bistability induced by serotonin in spinal motoneurons
Experimental Brain Research
|January 1, 1985
Summary
Serotonin uncovers a calcium-dependent plateau potential in turtle spinal motoneurons, revealing voltage-sensitive bistability. This finding highlights serotonin
Area of Science:
- Neuroscience
- Neurophysiology
- Motor Control
Background:
- Spinal motoneurons exhibit bistable states controlled by plateau potentials.
- Previous research suggested serotonin's involvement in this phenomenon in cats.
Purpose of the Study:
- To investigate serotonin's role in motoneuron plateau potential expression in an in vitro turtle spinal cord preparation.
- To elucidate the ionic mechanisms underlying serotonin-induced bistability.
Main Methods:
- Utilized an in vitro turtle spinal cord preparation.
- Applied serotonin directly to the bath solution.
- Tested the effects of manganese (Mn++) and tetrodotoxin (TTX) on motoneuron responses.
Main Results:
- Serotonin application induced a plateau potential and voltage-sensitive bistability in motoneurons.
- Serotonin-induced changes were blocked by Mn++.
- Plateau potential and bistability persisted after TTX application, indicating a calcium-dependent mechanism.
Conclusions:
- Serotonin modulates motoneuron intrinsic properties, revealing a previously uncharacterized plateau potential.
- The plateau potential is dependent on calcium influx.
- Serotonin controls the expression of this calcium-dependent plateau potential, impacting motoneuron excitability and bistability.
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