Histology of the Nervous System Flashcards
What are ependymal cells?
Low columnar or cuboidal cells that line the central canal of the spinal cord and the ventricle within the brain. In some places have cilia on apical surface to aid CSF flow. Different to epithelial cells –non basal laminar
What is the role of actin in neurons?
dynamic changes in morphology
What is the role of intermediate filaments in neurons?
permanent stability
What is the role of microtubules in neurons?
transport down the axon
What are nissl bodies?
a granular body of rough ER and ribosomes in neurons - for protein production
What are the passive support functions of astrocytes?
Neurotransmitter uptake and degradation K+ homeostasis Neuronal energy supply Maintenance of the BBB. Injury response and recovery
What are the active functions of astrocytes?
Modulation of neuronal function
Modulation of blood flow.
What initiates glia excitability?
neurotransmitters such as ATP, glutamate Trauma Spontaneous Inflammatory mediators.
What is the response of neurons to a calcium wave from glia?
inhibition - neurons become hyperpolarised
What is the response of blood vessels to the calcium wave from glia?
constriction
What types of cells myelinate in the CNS?
oligodendrocytes
What types of cells myelinate in the PNS?
schwann cells
What are the immune cells of the immune system called?
microglia
What is the difference between oligodendrocytes and schwann cells?
Oligodendrocytes can myelinate many axons but schwann cells can only myelinate one
What is a fasicle?
a bundle of nerve fibres - surrounded by perineurium
