Related Experiment Video
Updated: May 28, 2026
07:17
Aversive Associative Learning and Memory Formation by Pairing Two Chemicals in Caenorhabditis elegans
Published on: June 23, 2022
The A-current modulates learning via NMDA receptors containing the NR2B subunit
Ángela Fontán-Lozano1, Irene Suárez-Pereira, David González-Forero
1División de Neurociencias, Universidad Pablo de Olavide de Sevilla, Sevilla, Spain. angela.fontan@cabimer.es
Plos One
|October 4, 2011
Summary
Decreasing the A-type K(+) current (I(A)) lowers the threshold for learning and early long-term potentiation (early-LTP). This effect depends on NMDA receptors containing the NR2B subunit, highlighting a balance crucial for learning.
Area of Science:
- Neuroscience
- Molecular Biology
- Cognitive Science
Background:
- Synaptic plasticity underlies learning and memory but its molecular mechanisms remain incompletely understood.
- The transient A-type K(+) current (I(A)) is critical for regulating neuronal excitability in CA1 pyramidal neurons.
- I(A) influences action potential back-propagation and synaptic input integration.
Purpose of the Study:
- To investigate the impact of reduced I(A) on cognitive functions and synaptic plasticity.
- To explore the molecular players involved in I(A)-mediated regulation of learning.
Main Methods:
- Utilized wild-type mice treated with 4-AP (an I(A) inhibitor).
- Employed mice genetically deficient in the DREAM protein, a known I(A) modulator.
- Performed hippocampal electrophysiological recordings.
- Assessed learning and synaptic plasticity induction.
Main Results:
- Impairment of I(A) reduced the stimulation threshold for learning and early-LTP induction.
- Hippocampal recordings showed a shift towards low-theta frequencies in basal oscillatory properties.
- Facilitated learning due to decreased I(A) was dependent on NR2B-containing NMDA receptor activation.
Conclusions:
- A balance between I(A) and NR2B-containing NMDA receptor activity is essential for regulating learning.
- Modulating I(A) presents a potential therapeutic target for cognitive enhancement.
- Neuronal excitability and synaptic plasticity are intricately linked to learning processes.
Related Concept Videos
01:25Long-term Potentiation
Long-term potentiation, or LTP, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTP is the process of synaptic strengthening that occurs over time between pre and postsynaptic neuronal connections. The synaptic strengthening of LTP works in opposition to the synaptic weakening of long-term depression (LTD) and together are the main mechanisms that underlie learning and memory.
Hebbian LTP
LTP can occur when presynaptic neurons...
Hebbian LTP
LTP can occur when presynaptic neurons...
01:35Long-term Potentiation
Long-term potentiation, or LTP, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTP is the process of synaptic strengthening that occurs over time between pre- and postsynaptic neuronal connections. The synaptic strengthening of LTP works in opposition to the synaptic weakening of long-term depression (LTD) and together are the main mechanisms that underlie learning and memory.
01:30Ligand-Gated Ion Channel Receptor: Gating Mechanism
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
01:30Cognitive Enhancers: Cholinesterase Inhibitors and NMDA Receptor Antagonists
Cognitive enhancers, also known as "smart drugs," are substances used to enhance memory, mental alertness, and concentration. These can be natural or synthetic and improve cognition in conditions like Alzheimer's disease (AD) and other neurodegenerative diseases. Some common examples include caffeine, amphetamines, methylphenidate, modafinil, arecoline, donepezil, vortioxetine, and piracetam. These enhancers work on the principle of synaptic plasticity and altered circuit function. They...
01:15Cholinergic Receptors: Nicotinic
Nicotinic receptors are ligand-gated ion channels that are activated by acetylcholine and nicotine. Upon activation, they cause a rapid increase in the permeability of cells to K+, Na+, and Ca2+, followed by depolarization and excitation. They are in the autonomic ganglia, skeletal neuromuscular junction, CNS, and adrenal medulla.
There are two types of nicotinic receptors: neuromuscular (NM/NM/N1) and neuronal (NN/NN/N2). The two families differ based on their location and selectivity to...
There are two types of nicotinic receptors: neuromuscular (NM/NM/N1) and neuronal (NN/NN/N2). The two families differ based on their location and selectivity to...
01:19Ligand-gated Ion Channels
Ligand-gated ion channels are transmembrane proteins with a channel for ions to pass through and a binding site for a ligand. The channel opens only when a ligand attaches to the binding site.
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that include the...
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that include the...