Entorhinal Cortex Layer Iii Pyramidal Neurons is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Entorhinal Cortex Layer III Pyramidal Neurons constitute the primary hippocampal relay from the entorhinal cortex to the CA1 region. These neurons are critically involved in spatial navigation, memory encoding, and are among the first neurons to show tau pathology in Alzheimer's disease.
| Property |
Value |
| Category |
Cell Types |
| Brain Region |
Medial Temporal Lobe, Entorhinal Cortex |
| Neurotransmitter |
Glutamate (excitatory) |
| Cell Type |
Pyramidal neuron |
| Layer |
Layer III (L3) |
| Associated Diseases |
Alzheimer's Disease, Temporal Lobe Epilepsy, FTD |
| Taxonomy |
ID |
Name / Label |
| Cell Ontology (CL) |
CL:0000598 |
pyramidal neuron |
- Morphology: pyramidal neuron (source: Cell Ontology)
- Morphology can be inferred from Cell Ontology classification
| Database |
ID |
Name |
Confidence |
| Cell Ontology |
CL:0000598 |
pyramidal neuron |
Medium |
¶ Morphology and Markers
- Soma: Medium to large pyramidal cell bodies (20-30 μm)
- Dendrites: Prominent apical dendrites extending to layer I, basal dendrites
- Axon: Primary projection to CA1 stratum radiatum and lacunosum-moleculare
- Key Markers:
- RORβ (RORB) - layer-specific transcription factor
- Calbindin (CALB1)
- Cux1, Cux2 - upper layer markers
- Reelin (RELN) - secreted by Cajal-Retzius cells
- VR1 (CGRP receptor)
- Ephrins and Eph receptors
Entorhinal Cortex Layer II (Grid Cells) → Dentate Gyrus → CA3 (Pattern Separation)
Entorhinal Cortex Layer III (Border Cells) → CA1 (Pattern Completion)
-
Spatial Navigation:
- Provide head direction and border cell information to hippocampus
- Support spatial memory and navigation
- Critical for path integration
-
Memory Encoding:
- Relay information from association cortices to hippocampus
- Support episodic memory formation
- Integrate context and item information
-
Temporal Context:
- Time cells in EC L3 encode temporal sequences
- Support temporal ordering of memories
- Bridge过去 and present experiences
- Resting membrane potential: ~-65 mV
- Action potential threshold: ~-50 mV
- Firing pattern: Regular spiking, adapting
- Theta oscillations: Phase-locked firing during theta states
- Earliest vulnerability: EC L3 neurons show tau pathology before any other cortical region
- Braak staging: Stage I-II tau begins in EC L3 (transentorhinal cortex)
- Mechanisms:
- Tau propagation from EC L3 to hippocampus
- Selective vulnerability due to high metabolic demand
- Excitotoxicity from glutamate dysregulation
- Clinical correlation: EC L3 atrophy predicts MCI-to-AD progression
- Biomarker: CSF t-tau and p-tau reflect EC L3 neuronal loss
- Hyperexcitability: EC L3 neurons become hyperactive in TLE
- Aberrant sprouting: Axonal reorganization contributes to seizure spread
- Therapeutic target: mTOR inhibitors may reduce aberrant plasticity
- Tauopathy: EC L3 affected in some FTD subtypes
- Selective vulnerability: Different pattern than AD
NFT formation → Microtubule disruption → Impaired axonal transport
→ Synaptic dysfunction → Neuronal loss → Hippocampal disconnection
- Upregulated: RORB, CALB1, GRM1 (mGluR1), NMDAR1
- Vulnerability factors: High metabolic demand, calcium dysregulation
- Protective factors: CR (calretinin), SOM (somatostatin)
| Approach |
Target |
Status |
| Anti-tau antibodies |
Tau pathology |
Clinical trials |
| Tau aggregation inhibitors |
NFT formation |
Preclinical |
| Neurotrophic factors |
Neuronal survival |
Experimental |
| Neuroprotective agents |
Excitotoxicity |
Clinical trials |
| Deep brain stimulation |
EC-CA1 circuit |
Experimental for AD |
| Feature |
Layer II (Grid Cells) |
Layer III (Border Cells) |
| Target |
Dentate Gyrus, CA3 |
CA1 |
| Function |
Spatial metric |
Contextual/boundary |
| Pathology |
Later in AD |
Earlier in AD (first!) |
| Cell type |
Stellate-like |
Pyramidal |
- [Entorhinal Cortex Layer II Stellate Cells
- Hippocampal CA1 Pyramidal Neurons
- Hippocampal CA3 Pyramidal Cells
- Dentate Gyrus Granule Cells](/cell-types/entorhinal-cortex-layer-ii-stellate-cells
--hippocampal-ca1-pyramidal-neurons
--hippocampal-ca3-pyramidal-cells
--dentate-gyrus-granule-cells)
- Alzheimer's Disease
- Entorhinal Cortex
- Medial Temporal Lobe
The study of Entorhinal Cortex Layer Iii Pyramidal Neurons has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.