Horizontal cells of Cajal (HCCs) are small, bipolar neurons located in the marginal (layer I) cortex of the developing brain. Originally described by Santiago Ramón y Cajal in the late 19th century, these cells represent an evolutionarily conserved transient neuronal population that plays crucial roles in cortical development. While largely absent in adult mammals, residual populations have been identified in humans and non-human primates, with emerging evidence suggesting potential roles in cortical plasticity and disease processes. [1]
| Property | Value | [2]
|----------|-------| [3]
| Category | Developmental Neurons | [4]
| Location | Cortical layer I, subpial zone | [5]
| Cell Types | Horizontal cells of Cajal, subpial neurons | [6]
| Primary Neurotransmitter | GABA (primarily), Glutamate (subpopulations) | [7]
| Key Markers | Reelin, Calretinin, Calbindin, Nissl substance | [8]
| Taxonomy | ID | Name / Label |
|---|---|---|
| Cell Ontology (CL) | CL:0000695 | Cajal-Retzius cell |
| Database | ID | Name | Confidence |
|---|---|---|---|
| Cell Ontology | CL:0000695 | Cajal-Retzius cell | Exact |
| Species | Adult Presence | Density |
|---|---|---|
| Mouse | Minimal/absent | Very low |
| Rat | Trace populations | Low |
| Rabbit | Moderate | Moderate |
| Human | Documented | Variable |
| Non-human primate | Documented | Higher than rodents |
The study of Horizontal Cells Of Cajal 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.
Soriano et al. Reelin signaling in cortical development (2021). 2021. ↩︎
Tissir & Goffinet, Reelin and brain development (2003). 2003. ↩︎
Ramos-Moreno et al. Endogenous Reelin in adult brain (2022). 2022. ↩︎
Choi et al. Horizontal cells in Alzheimer's disease (2020). 2020. ↩︎
Frotscher et al. Role of Reelin in synapse formation (2014). 2014. ↩︎
Bock & May, Cajal's horizontal cells in primates (2011). 2011. ↩︎
Huang et al. GABAergic dysfunction in neurodegeneration (2023). 2023. ↩︎