Neurotransmitterrs Flashcards
Glia
Astro Yates, oligodendrocytes and Schwann cells and microglia
Dendrites
Input, increase contact expanse
Dendritic spines
Increase SA for axonal contact
Cell body
Maintenance factory
Axon
Output, can reach distances far away
Myelin sheath
Insulation for electrical signaling
Synaptic buttons
Chemical signaling, neurotransmitters
Axon hillock
Action potential generated
Sensory neurons
Receptors in periphery, cell body in ganglion
Motor neurons
Cell body in CNS for skeletal motor neurons
Cell body in autonomic ganglia for smooth muscle
Interneurons
Contained in CNS
Travel from one brain region to another and local confined to cell body
Internal structure neurons
High protein synthesis and neurotransmitter
Ribosomes and rough ER
cytoskeleton components- microtubules, neurofilsments and microfilaments
Spinal cord circuitry
Gray matter in 10’layers, Latina
Peripheral into spinal cord via dorsal roots and dorsal root ganglia contain cell bodies of sensory axons
Ventral horn and intermediate zone contain cell bodies of motor neurons whose axons travel in ventral root
Peripheral nerves
Epineurium, perineurium snd endoneurium
Epineurium
Fibroblasts and collagen sheath containing peri and epineurium and peripheral axons
Perineurium
Connective tissue sheath containing bundles of peripheral nerve axons
Endoneurium
Connective tissue sheath surrounding individual axons
Schwann cell
Unmyelinated in PNS
Glial cell factors
Do not form synapses
Electrically unexcitable, no action potential
Only 1 process and some divide, numerous as neurons
Astrocytes
Provide structural matrix- blood brain barrier
Homeostasis- K and glucose, and neurotransmitters
Scar following injury
Many different types and shapes
Blood brain barrier
Surrounding capillary with endothelial cells forming tight junction
Pedicures with smooth muscle like property and astroglial end feet
Myelin producing cells
Oligodendrocytes and Schwann cells
1 oligo forms many myelin segments CNS and insulate against signal degradation
Segmentally organized nodes of Ranvier
Schwann cells can act like CNS glial cells but are PNS, create ECM and can phagocytose
Microglia
Ubiquitous, numerous, plasticity, immune competence- can become brain macrophages and self renewal
Ependymal cells
Line ventricular system
Circulate CSF via cilia
Choroid plexus cells produce and secrete CSF
CSF during sleep removes metabolites
Three compartments and three interfaces
Blood-CNS
CNS-CSF
CSF- blood
So glucose can pass through blood brain barrier
Cerebral cortex
6 layers
Pyramidial cells (3 and 5)
Long axons of cortex
Projects to other neurons in cerebral cortex
Projects structures outside cerebral cortex
Layer 4 is the inner granular layer and receives info from thalamus