Hippocampal Bistratified Cells <table class="infobox infobox-cell">
<tr>
<th class="infobox-header" colspan="2">Hippocampal Bistratified Cells</th>
</tr>
<tr>
<td class="label">Taxonomy</td>
<td>ID</td>
</tr>
<tr>
<td class="label">Cell Ontology (CL)</td>
<td>[CL:0004247](https://www.ebi.ac.uk/ols4/ontologies/cl/classes/http%253A%252F%252Fpurl.obolibrary.org%252Fobo%252FCL_0004247)</td>
</tr>
<tr>
<td class="label">Condition</td>
<td>Bistratified Cell Effect</td>
</tr>
<tr>
<td class="label">Alzheimer's Disease</td>
<td>Early vulnerability</td>
</tr>
<tr>
<td class="label">Temporal lobe epilepsy</td>
<td>Loss of function</td>
</tr>
<tr>
<td class="label">Hippocampal sclerosis</td>
<td>Severe depletion</td>
</tr>
<tr>
<td class="label">Normal aging</td>
<td>Gradual decline</td>
</tr>
<tr>
<td class="label">Schizophrenia</td>
<td>Circuit dysfunction</td>
</tr>
</table>
Introduction ...
Hippocampal Bistratified Cells <table class="infobox infobox-cell">
<tr>
<th class="infobox-header" colspan="2">Hippocampal Bistratified Cells</th>
</tr>
<tr>
<td class="label">Taxonomy</td>
<td>ID</td>
</tr>
<tr>
<td class="label">Cell Ontology (CL)</td>
<td>[CL:0004247](https://www.ebi.ac.uk/ols4/ontologies/cl/classes/http%253A%252F%252Fpurl.obolibrary.org%252Fobo%252FCL_0004247)</td>
</tr>
<tr>
<td class="label">Condition</td>
<td>Bistratified Cell Effect</td>
</tr>
<tr>
<td class="label">Alzheimer's Disease</td>
<td>Early vulnerability</td>
</tr>
<tr>
<td class="label">Temporal lobe epilepsy</td>
<td>Loss of function</td>
</tr>
<tr>
<td class="label">Hippocampal sclerosis</td>
<td>Severe depletion</td>
</tr>
<tr>
<td class="label">Normal aging</td>
<td>Gradual decline</td>
</tr>
<tr>
<td class="label">Schizophrenia</td>
<td>Circuit dysfunction</td>
</tr>
</table>
Introduction
Mermaid diagram (expand to render)
Hippocampal bistratified cells are a major class of somatostatin-expressing inhibitory interneurons that target both the soma and dendrites of CA1 pyramidal neurons. Their distinctive axonal projection pattern, targeting both stratum radiatum and stratum oriens, gives them their "bistratified" nomenclature. These cells play crucial roles in regulating hippocampal circuit activity, controlling synaptic integration, and supporting hippocampal-dependent learning and memory.
<!-- multi-taxonomy-enrichment -->
Multi-Taxonomy Classification
Taxonomy Database Cross-References
External Database Links
[Cell Ontology (CL:0004247)](https://www.ebi.ac.uk/ols4/ontologies/cl/classes/http%253A%252F%252Fpurl.obolibrary.org%252Fobo%252FCL_0004247)
[OBO Foundry (CL:0004247)](http://purl.obolibrary.org/obo/CL_0004247)
[Allen Brain Cell Atlas](https://portal.brain-map.org/atlases-and-data/bkp/abc-atlas)
[CellxGene Census](https://cellxgene.cziscience.com/)
[Human Cell Atlas](https://www.humancellatlas.org/)
Anatomical Location Hippocampal bistratified cells are positioned in the:
CA1 region : Primarily in the stratum oriens near the pyramidal layerSoma location : Typically at the stratum pyramidale/stratum oriens boundaryDistribution : Throughout the septal-temporal axis of CA1Density : Moderate density compared to other interneuron typesLaminar specificity : Axons target both stratum radiatum (apical dendrites) and stratum oriens (basal dendrites)[@lei2004]Connectivity
CA3 Schaffer collateral axons : Primary excitatory inputCA1 pyramidal neurons : Feedback connectionsLocal interneurons : GABAergic modulationCholinergic fibers : From medial septum diagonal bandSerotonergic fibers : From raphe nucleiGABAergic inputs : From other interneuronsVIP-positive interneurons : Disinhibitory inputs[@freund1996]Efferent Outputs (Outgoing Connections)
CA1 pyramidal neuron somata : Somatic inhibitionCA1 apical dendrites : Dendritic inhibition in stratum radiatumCA1 basal dendrites : Dendritic inhibition in stratum oriensOther bistratified cells : Cross-inhibitory networksOther CA1 interneurons : Feedforward inhibition circuitsMorphology
Cellular Structure
Soma : Medium-sized, oval-shaped cell bodiesAxonal projections : Characteristic dual-strata axonal arborizationStratum radiatum axons : Target apical dendritesStratum oriens axons : Target basal dendritesDendrites : Radially oriented, extending through multiple layersAxon collaterals : Extensive, highly branched terminal fieldsMolecular Signature
Somatostatin (SST) : Primary defining markerCalbindin (CALB1) : Often co-expressedReelin (RELN) : Partial expressionParvalbumin (PV) : Typically negativeNeurotensin : Subset expressionGABA : Primary inhibitory neurotransmitter[@maccaferri2006]Neurophysiology
Firing Properties
Spike pattern : Regular spiking with adaptationAccommodation : Strong spike frequency accommodationAction potential : Broad action potentials (0.5-1.0 ms duration)Resting potential : Approximately -65 to -70 mVInput resistance : Moderate (100-200 MΩ)Active Properties
Hyperpolarization-activated current (Ih) : Depolarized reversal potentialAfterhyperpolarization : Prominent AHP following spikesDepolarizing envelope : Subthreshold oscillationsSynaptic integration : Linear summation propertiesNormal Function
Dendrosomatic Integration Control Bistratified cells provide comprehensive inhibition:
Somatic targeting : Controls action potential generationDendritic targeting : Regulates synaptic input integrationCoordinated inhibition : Simultaneous somatic and dendritic inhibitionInput-specific modulation : Can selectively inhibit specific dendritic domainsFeedforward Inhibition
Receive CA3 input : Activated by Schaffer collateral afferentsRapid onset : Fast feedforward inhibition (~2-5 ms latency)Gain control : Modulate excitation-to-inhibition ratioTemporal sharpening : Enhance temporal precision of CA1 activationFeedback Inhibition
Respond to CA1 output : Activated by pyramidal neuron firingRecurrent circuit : Part of CA1 inhibitory networkHomeostatic regulation : Prevent overexcitationTheta Oscillations
Phase-locked firing : Fire at specific theta phasesCoordinate timing : Synchronize pyramidal neuron activitySpatial processing : Support place cell firingMemory consolidation : Facilitate hippocampal-cortical dialogRole in Neurodegeneration
Alzheimer's Disease
SST+ neuron vulnerability : Bistratified cells are among vulnerable interneuronsEarly changes : Loss precedes pyramidal neuron degenerationCircuit dysfunction : Impairs hippocampal memory circuitsFunctional impact : Contributes to spatial memory deficitsMechanisms : Amyloid toxicity, tau pathology, calcium dysregulation[@palop2016]Epilepsy
Feedforward inhibition loss : Disrupted in epileptic tissueHyperexcitability : Contributes to seizure generationNetwork instability : Altered inhibitory controlTherapeutic target : Restoration of bistratified functionOther Neurodegenerative Conditions
Temporal lobe epilepsy : Loss of bistratified cellsHippocampal sclerosis : Severe depletionNormal aging : Gradual decline in SST+ interneuronsSchizophrenia : Altered bistratified cell functionDisease Associations
See Also
[Somatostatin-Positive Interneurons
[Hippocampal CA1 Pyramidal Neurons](/cell-types/ca1-pyramidal-neurons)
Hippocampal Interneuron Types](/cell-types/somatostatin-positive-interneurons
--hippocampal-ca1-pyramidal-neurons
--hippocampal-interneuron-types)
[Alzheimer's Disease](/diseases/alzheimers-disease)
External Links
[Cell Type Database](https://portal.brain-map.org/)
[PubMed: Cell Type Markers](https://pubmed.ncbi.nlm.nih.gov/)
Pathway Diagram The following diagram shows the key molecular relationships involving Hippocampal Bistratified Cells discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)
Show full description