L1 CELLS Flashcards
Neurons and astrocytes
4 different polarities of neurons ?
Unipolar
Pseudounipolar
Bipolar
Multipolar
5 different neuronal circuits ?
Divergence- one to many
Convergence- many to one
Serial processing- sequential neurons
Parallel processing- neurons pools/sequences process info simultaneously
Reverberation- excitatory or inhibitory feedback mechanism
Give an example of a microtubule stabilising protein found in dendrites?
MAP2B
What are the different types of spines?
Stubby, thin, mushroom, filopodium
List components of the axon and synapse
Neurofilaments in axon (strength) Microtubules Tau (microtubule stablising protein) Cell adhesion molecules (L1,TAG1) Neurotransmitters SNARE complexes Golgi Smooth ER Mitochondria
List components in Astrocytes.
GFAP, microtubules, actin Vimentin Glycogen granules Mitochondria Golgi ,Rough ER Large Nucleus Light cytoplasm
What are the 4 types of astrocytes and where are they found?
Grey Matter (Low GFAP, connect with neurons and vessels)
Fibrous Astrocytes (white matter- high in GFAP, connect with oligodendrocytes and axons).
Cerebellum Velate astrocytes
Bergmann Glial cells
What are some functions of Astrocytes?
Modulate synaptic function Maintain BBB Mediate extracellular environment Maintain ion gradients Clear cellular debris Metabolism- Cholesterol & Lactate production Release of growth factors- neuroprotection. Recycle neurotransmitters Anti-inflammatory cytokines
How can astrocytes go wrong?
Formation of Glial scar Increased excitotoxicity. Increased calcium and ATP release. Increased nitric oxide production Superoxide dismutase accumulation
Blue, Orange, Purple- 3 cool functions of astrocytes?
- Aquaporin 4 (AQP4) in end-feet. Regulates extracellular space, CSF flow, metabolic waste clearance, Ca2+ signalling and neuroinflammation.
- Secretion of neuronal trophic factors (GDNF,FGF,IGF)
- Potassium recevoir. Remove extracellular K+, keeping levels low for optimal neuronal ion concentration gradient. K+ redistributed to other regions- “spatial buffering” of potassium.
Even more functions of astrocytes? (Bonus points)
Supply lactate to neurons Only cells storing glycogen in brain! Provude neurons with cholesterol. Synthesise apolipoprotein E. Structural support (Bergmann in cerebellum, Muller in retina).
Even more functions of astrocytes? (Bonus points)
Supply lactate to neurons Only cells storing glycogen in brain! Provide neurons with cholesterol. Synthesise apolipoprotein E. Structural support (Bergmann in cerebellum, Muller in retina).
