Neural Tissue Lab Flashcards
Other names for cell body
Perikaryon and soma
Products of cell body RER
cytoskeletal elements transport and secretory proteins
What type of neuron has a real abundance of Nissl bodies?
Motor
In a neuron, where can we find golgi?
Cell body only
In the neuron, where can we find mitochondria?
Anywhere
Most commonl ocations for mitochondria?
Cell body and axon terminals
What are neurofilaments?
Intermediate filaments in neurons
How do we visualize neurofilaments?
when cross-linked w/certain fixatives, these retain silver stains well, visible with Light Microscope!
What other pigments can we see in neurons?
Lipofuscin and others due to lysosomal digestion/aging because neurons are long-lived cells
Terminal arborization?
Distal end of the axon
Types of movement along an axon
Anterograde and retrograde
Anterograde movement
Kinesin takes thing from cell body down to end of axon
Retrograde movement
Synaptic terminal back to cell body via Dynein
Glial CNS cells
Oligodendrocytes Astrocytes Microglial cells Ependymal cells
Main function of oligodendrocytes
produce myelin sheaths around axons in the CNS, able to branch and ensheath parts of more than one axon! provide electrical insulation
What is the predominant glial cell in the CNS white matter?
Oligodendrocyte
Why is it called “White” matter?
High lipid concentration
Main functions of Astrocytes
- Structural and metabolic support of neurons 2. Contribute to BBB 3. Initiate/Aid repair processes
How do Astrocytes provide structural and metabolic support of neurons?
- guides developing neurons in the CNS - regulates extracellular ion concentrations, esp K+ buffering - regulates vasodilation - moves nutrients, wastes, etc b/w neurons and capillaries
How do Astrocytes contribute to BBB?
- extensions called perivascular feet cover capillary endothelium - expanded processes form a barrier layer (glial limiting membrane) - lines the meninges @ the external CNS surface
Types of astrocytes?
Fibrous Protoplasmic
Fibrous astrocytes?
predominate in white matter, have relatively few but long processes
Protoplasmic astrocytes?
Predominate in gray matter ave many but shorter, branched processes
GFAP?
larger processes of all astrocytes reinforced with glial fibrillary acid protein (GFAP). Common source of brain tumors
Frequency of astrocytes vs. oligodendrocytes?
most numerous in the CNS. don’t confuse w/predominance of oligodendrocytes - they’re just the most prevalent in the white matter of the CNS
Type of stain to see astrocytes
Cajal’s. Blackens astrocytes
Main function of microglial cells?
defense & immune-related activities (cytokine secretion)
Histology oligodendrocytes
Oligodendrocytes have nuclei that are small, round and stained very densely
Microglial cells on histology
The microglial cell bodies are thinner and usually elongated (they have short irregular processes that require special stains to identify)
Where do we find ependymal cells?
line ventricles of the brain & the central canal of the spinal cord
Structural features of ependymal cells
some cellular apices have cilia that facilitate CSF movement some have long microvilli (likely for absorption)
Another name for a schwann cell?
neurolemmocyte
Satellite cells of ganglia
structural & metabolic support for neuronal cell bodies form a tight covering/layer over larger neuronal cell bodies of ganglia in the PNS
Anaxonic neuron
No true axon, many dendrites
Divisions of gray matter
Posterior dorsal horn Anterior ventral horn
Posterior/dorsal horn
sensory receive sensory input from dorsal root ganglia
Anterior/ventral horns
motor axons make up ventral roots of spinal nerves
Central canal?
aka gray commissure joins the posterior and anterior horns
What cells line the central canal?
Ependymal Cells
Nissl bodies/ Rough ER
Node of Ranvier
A vs. B
Myelinated (B) vs unmyelinated (A) nerves
note the white, circular spaces where the fatty sheath surrounds the axon
Neuronal cell body (A), glial cell body (B), axons (C)
From Left to Right: Epineurium (far left and thick), Perineurium (Flattened nuclei, borders both sides of the white space), Endoneurium (outlines of little circles on the right)
All other Neural information provided in the other neural flash cards
Hoo-Ah
