Cells of the Nervous System 2 Flashcards
What is neuronal integration?
Integration of competing inputs in the postsynaptic neurone
3 types of synapse and their nature?
Axo-dendritic - excitatory
Axo-somatic - inhibitory
Axo-axonic - modulatory
Support cells of CNS?
Astroglia
Oligodendroglia
Microglia
Ependymal cells
Support cells of PNS?
Schwann cells
Satellite glia
Features of astroglia?
Star-shaped Most abundant CNS cell type 3 types Numerous intermediate filament bundles Gap junctions
3 types of astroglia?
Fibrous (white matter)
Protoplasmic (grey matter)
Radial
Functions of astroglia?
Scaffold for neuronal migration and axon growth during development
Formation of blood-brain barrier and brain-CSF barrier
Transport of substances from blood to neurones
Removal and degradation of neurotransmitters
Neuronal-glial/glial-neuronal signalling
Oligodendroglia features?
Small spherical nuclei
Prominent ER and Golgi
No intermediate filaments
Highly metabolically active
Oligodendroglia function? (crucial)
Production/maintenance of myelin sheath
Myelin features?
Lipid-rich insulating membrane
Up to 50 lamellae
Dark and light bands
Highly susceptible to damage
Microglia features and types?
Macrophages
Dense lysosomes, lipid droplets and residual bodies
3 categories based on morphology, Resting Ramified, Rod-like, Activated
Functions of microglia?
Macrophage population of CNS
Immune surveillance and antigen presentation
First cells to react to infection/damage
What are ependymal cells and where do you find them?
Epithelial-type cells which line ventricles and central canal of spinal cord
Ependymal cell features?
Apical microvilli and cilia
Prominent gap junctions between cells
No tight junctions
Peripheral nervous system support cell types?
Schwann cells
Satellite cells
What are Schwann cells and what do they do?
Produce myelin - only one myelin sheath per cell
Envelope axons of sensory and motor neurones in the PNS
Also perform functions of astrocytes
Promote axon regeneration
What are satellite cells and what do they do?
Provide metabolic support
Surround neuronal cell bodies in spinal ganglia
Perform functions of astrocytes from GREY matter of the CNS (protoplasmic)
Two types of oligodendroglia and where are they found?
Interfascicular - found in rows along axon tracts
Perineuronal - found in association with neuronal cell bodies
