HISTOLOGY - NERVOUS SYSTEM

• ends of axons with branches

  telodendria
• multipolar cells are usually found in:

  interneurons and in motor neurons of the CNS
• bipolar neuron found in:


  retina of eye, inner ear, olfactory nerve
• unipolar neuron


  spinal and cranial dendria
• • provide structural support
  • maintains BBB (blood brain barrier)
  • supplying energy for metabolism
  • scavenging ions or debris
  • presence of intermediate filament marker
  • useful in identifying presence of astrocytes


  ASTROCYTES
• intermediate filament marker of an astrocyte

  glial fibrillar acidic protein
• short, gfap, gray matter in astrocytes

  protoplasmic
• long, white matter in astrocytes

  fibrous
• • poached egg appearance
  • formation of myelin sheaths

  OLIGODENDROCYTES
• functions as a phagocyte, dense elongated structure

  MICROGLIAL/GLIAL CELLS
• • line central canal and ventricles of the CNS
  • apical processes in free-surface that have cilia
  • movement of CSF
  • have microvilli for absorption
  • columnar or cuboidal


  EPENDYMAL CELLS
• SCHWANN CELLS

  • counterpart of an oligodendrocyte
  • axon formation
• SATELLITE CELLS

  • support to neurons
  • regulating exchange of material
  • pigment of lipofuscin
• • site of communication between a neuron and another cell
  • ensures that the direction is unidirectional

  SYNAPSE
• • synaptic vesicles
  • neurotransmitters via exocytosis
  • synaptic end bulbs


  PRESYNAPTIC AXON TERMINAL
• post synaptic cell membrane

  • binder receptors
  • neurotransmitter receptors
• • dura mater
  • outermost
  • thick ct layer two layers periostial and meningal layer
  • fused but in brain they are separated to form dural venous sinuses
  • spaces found between the two layers filled with blood
  • spinal cord
  • between is the epidural space
• • arachnoid mater
  • thin space between arachnoid matter and dura
  • subdural space
  • sheath of CT tissue and presence of trabecula (fibroblast and collagen) inside has sponge-like cavity (subarachnoid space) that has CSF
• • pia mater
  • flattened mesenchymal derived cells
  • no contact with nerve cells
  • the mesenchymal layer of astrocytic processes
  • glia limitans