Related Experiment Video
Updated: Jun 26, 2026
10:00
Physiological Recordings of High and Low Output NMJs on the Crayfish Leg Extensor Muscle
Published on: November 17, 2010
State-, timing-, and pattern-dependent neuromodulation of synaptic strength by a serotonergic interneuron
1Neuroscience Institute, Georgia State University, Atlanta, Georgia 30302-5030, USA. akira@gsu.edu
Summary
A single serotonergic neuron in Tritonia diomedea controls synaptic strength through two distinct actions. One action resets potentiation, while the other enhances synaptic strength, influencing motor patterns.
Area of Science:
- Neuroscience
- Synaptic Plasticity
- Neuromodulation
Background:
- Synaptic plasticity underlies learning and memory.
- Serotonergic neurons modulate neural circuits.
- Motor patterns involve complex synaptic interactions.
Purpose of the Study:
- To investigate the distinct neuromodulatory actions of a serotonergic neuron.
- To understand the state and firing pattern dependencies of these actions.
- To elucidate the role of these actions in motor pattern regulation.
Main Methods:
- Electrophysiological recordings in the mollusc Tritonia diomedea.
- Measurement of excitatory postsynaptic currents (EPSCs).
- Application of serotonin and receptor antagonists.
Main Results:
- A serotonergic neuron (DSI) exhibits two distinct actions on VSI synapses.
- One action is state-dependent, resetting synaptic potentiation.
- The other action is state-independent, enhancing synaptic strength.
Conclusions:
- Serotonergic neuromodulation is complex, with context-dependent effects.
- Distinct actions allow fine-tuning of motor patterns.
- State-dependent and independent mechanisms contribute to neural circuit function.
Related Concept Videos
01:28Integration of Synaptic Events
Synaptic integration mainly includes the summation of graded potentials. Graded potentials, regardless of their type, cause subtle alterations in membrane voltage, resulting in either depolarization or hyperpolarization. These incremental changes, when combined or summed, can propel the neuron toward its threshold. Consider, for example, a membrane experiencing a +15 mV shift, causing it to depolarize from -70 mV to -55 mV. In this scenario, graded potentials govern the membrane's ability to...
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
01:26Neurochemical Transmission: Sites of Drug Action
Neurochemical transmission, the conduction of electrical impulses between neurons mediated by neurotransmitters, plays a vital role in various physiological processes. Autonomic drugs exert their effects by modulating neurotransmission within the autonomic nervous system. For instance, drugs such as hemicholinium block the precursor uptake necessary for synthesizing acetylcholine, an essential autonomic neurotransmitter. Following synthesis, neurotransmitters are stored in vesicles. Metyrosine...
01:09Synaptic Signaling
Neurons communicate at synapses, or junctions, to excite or inhibit the activity of other neurons or target cells, such as muscles. Synapses may be chemical or electrical.
Most synapses are chemical, meaning an electrical impulse or action potential spurs the release of chemical messengers called neurotransmitters. The neuron sending the signal is called the presynaptic neuron, and the neuron receiving the signal is the postsynaptic neuron.
The presynaptic neuron fires an action potential that...
Most synapses are chemical, meaning an electrical impulse or action potential spurs the release of chemical messengers called neurotransmitters. The neuron sending the signal is called the presynaptic neuron, and the neuron receiving the signal is the postsynaptic neuron.
The presynaptic neuron fires an action potential that...
01:12Synaptic Signaling
Neurons communicate at synapses, or junctions, to excite or inhibit the activity of other neurons or target cells, such as muscles. Synapses may be chemical or electrical.