Betz cells (giant pyramidal neurons in primary motor cortex) are among the earliest and most severely affected neurons in ALS.
Betz cells are the largest pyramidal neurons in the human brain, with cell bodies in layer V of the primary motor cortex.
- Giant pyramidal cell bodies (up to 30μm)
- Very long apical dendrites
- Extensive dendritic arborization
- Low threshold for action potential generation
- High firing rates during movement
- Direct corticospinal projections
- Progressive proximal dendrite degeneration
- Synaptic input loss
- TDP-43 pathology
- Excitotoxicity: High glutamate sensitivity
- Oxidative Stress: High metabolic demand
- Mitochondrial Dysfunction: Energy deficit
- Neuroinflammation: Microglial activation
- Betz cell loss correlates with clinical weakness
- Preclinical changes before symptom onset
- Betz cell loss as progression marker
- Neurophysiological markers (TMS)
- Excitotoxicity modulation
- Neuroprotection strategies
- Betz cells in ALS (2022)
- Cortical hyperexcitability in ALS (2021)