Term
| What are the 2 main classes of cells in the nervous system? |
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Definition
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Term
| Are there more glia or nerve cells? |
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Definition
|
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Term
| What are the 2 subcategories of glia cells? |
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Definition
|
|
Term
| What 3 cells are considered macroglia? |
|
Definition
1) oligodendrocytes
2) Schwann cells
3) astrocytes |
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Term
Function
Oligodendrocytes & Schwann cells |
|
Definition
| produce myelin & insulate never cell axons (saltatory conduction) |
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Term
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Definition
| act as scavengers - remove debris after cell death |
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Term
| How do glial cells promote signaling b/w neurons? |
|
Definition
| accumulating or metabolizing neurotransmitters |
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Term
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Definition
1) guide migrating neurons
2) neuronal progenitors in some brain regions (hippocampus) |
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Term
| What cells regulate the properties of the presynaptic terminal at the nerve-muscle synapse? |
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Definition
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Term
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Definition
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Term
| What do glial cells synthesize & release for neuronal survival? |
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Definition
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Term
| What 3 physical supports do glial cells have? |
|
Definition
1) neuron support
2) structure to brain
3) separate & insulate neuronal groups/synaptic connections |
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|
Term
| What are the main signaling units of the nervous system? |
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Definition
|
|
Term
| What are the 4 parts of a neuron? |
|
Definition
1) cell body (soma)
2) dendrites
3) axon
4) presynaptic terminals |
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Term
|
Definition
| metabolic center containing nucleus & ER |
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Term
|
Definition
| tree-like processes with extensive arborization to recieve incoming signals |
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Term
| What receptors are available on dendrites? |
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Definition
| ionotropic neurotransmitter receptors (glutamatergic) & voltage gated Ca2+ channels |
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Term
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Definition
| recieve signal & propagate electrical signal to the soma |
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Term
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Definition
| output unit for the neuron |
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Term
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Definition
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Term
| What receptors do axons use to convey action potentials? |
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Definition
| voltage-gated Na+ channels |
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Term
| Where are action potentials initialized? |
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Definition
|
|
Term
| Where are presynaptic terminals found on a neuron? |
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Definition
| at the end of the dividing branches of the axon |
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|
Term
Function
presynaptic terminals of the neuron |
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Definition
| "classical" neurotransmitter biosynthesis (package to synaptic vesicles & exocytosis) |
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Term
| How do neurons connect with eachother? |
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Definition
|
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Term
| What parts of the 2 neurons can be synaptically connected? |
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Definition
1) axo-dendritic
2) axo-somatic
3) axo-axonic |
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Term
| Why is it important to understand the steps involved in synaptic transmission? |
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Definition
| each of these steps can be targeted for pharmocological intervention |
|
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Term
| How many steps are involved in synaptic transmission? |
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Definition
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|
Term
Synaptic transmission
Step 1 |
|
Definition
| Neuron synthesizes neurotransmitter from precursor & stores in vesicles |
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Term
Synaptic transmission
Step 2 |
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Definition
| Action potential travels down axon & depolarizes pre-synaptic nerve terminal |
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|
Term
Synaptic transmission
Step 3 |
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Definition
| Membrane depolarization activates voltage-dependent Ca2+ channels => Ca2+ to enter pre-synaptic nerve terminal |
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|
Term
Synaptic transmission
Step 4 |
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Definition
| Increased cytosolic Ca2+ => vesicle fusion with plasma membrane => neutrotransmitter release to synaptic cleft |
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Term
Synaptic transmission
Step 5 |
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Definition
Neurotransmitter crosses synaptic cleft & binds to:
1) ionotropic receptors => change in permeability or membrane potential
or
2)metabotropic receptors => cascade to activate other ion channels |
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|
Term
Synaptic transmission
Step 6 |
|
Definition
Signal termination via:
1) degrading transmitter via enzymes in cleft
or
2) transmitter recycled to presynaptic cell by reuptake transporters |
|
|
Term
Synaptic transmission
Step 7 (continuation of 6) |
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Definition
| Signal termination also via enzymes that degrade post-synaptic cell signaling molecule |
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Term
|
Definition
| 1)Neurotransmitter synthesized & packaged
2) action potential down axon
3) Ca2+ channels activated my membrane depolarization
4) increased Ca2+ => vesicle fusion => neurotransmitter release to synaptic cleft
5)Neurotransmitter binds to:
a) ionotropic receptor => Δ permeability & membrane potential
b) metabotropic receptor => cascade => Δ permeability
6)Signal termination by:
a) enzyme degradation in synaptic cleft
b) recyled via reuptake transporters in presynaptic cell
7)Signal termination via enzymes degrading postsynaptic signaling molecules |
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|
Term
| What are the 2 borad categories of small molecule neurtransmitters? |
|
Definition
1) aa (amino acids)
2) biogenic amines |
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|
Term
Function
aa as neurotransmitters |
|
Definition
| primary excitatory & inhibitory neurotransmitters in CNS |
|
|
Term
Function
biogenic amines as neurotransmitters |
|
Definition
| primary modulatory neurotransmitters in CNS |
|
|
Term
| What neurotransmitter structural category (aa or biogenic amines) do Ach, adenosine, NO, & peptide neurotransmitters fall into? |
|
Definition
|
|
Term
| How is NO an atypical neurotransmitter? |
|
Definition
| made on demand & released by diffusion (not by synaptic vesicles) |
|
|
Term
| Where are peptide neurotransmitters of hte brain typically found? |
|
Definition
| co-localized with classical neurotransmitters |
|
|
Term
| How are peptide neurotransmitters synthesized? |
|
Definition
| from large precursors & cleaved via specific proteases |
|
|
Term
| Where in the nerve are peptide neurotransmitters synthesized? |
|
Definition
| In the soma & are transported down the axon |
|
|
Term
| Which aa do most neurons in the brain use as the neurotransmitter to mediate fast excitatory synaptic transmission? |
|
Definition
|
|
Term
| How does glu mediate fast synaptic transmission? |
|
Definition
| activating ligand gated ion channels (ionotropic receptors) of AMPA & NMDA |
|
|
Term
| What happens when glu activated the ionotropic receptors? |
|
Definition
| depolarize membrane via Na+ & Ca2+ passage down electrochemical gradients |
|
|
Term
| What receptors mediate inhibitory neurotransmission? |
|
Definition
| GABA or glycine activation of other ionotropic receptors |
|
|
Term
| How do GABA & glycine mediate inhibitory neurotransmission? |
|
Definition
| hyperpolarize the membrane via movement of Cl- down its gradient |
|
|
Term
| What determines the output of a neuron? |
|
Definition
| The sum of its inhibitory & excitatory parts |
|
|
Term
Function
metabotropic G protein-coupled receptors |
|
Definition
| modulating the properties of the neurons themselves => modulates hoe they integrade fast synaptic activity |
|
|
Term
|
Definition
| heterotrimeric proteins that couple receptor activation with various effector mechanisms |
|
|
Term
| What mediates the actions of G protein coupled receptors? |
|
Definition
| a variety of second messanger systems s.a. cAMP-PKA system. |
|
|
Term
| What in the properties of the second messenger systems allows for pharmalogical intervention at numerous places? |
|
Definition
| the biological complexity within the signaling pathway |
|
|
Term
| How can G protein coupled receptors add additional layers of complexity? |
|
Definition
| Same neurotransmitter interacts with multiple metabotropic receptors that have different second messanger affects |
|
|
Term
| What happens when you stimulate Gαs?
Gαq?
Gαi/o? |
|
Definition
| Gαs: increased AC
Gαq: increased PLCβ
Gαi/o: decreased AC |
|
|
Term
| What G receptor do β adrenergic receptors stimulate? |
|
Definition
|
|
Term
| What G receptor do α1 adrenergic receptors stimulate? |
|
Definition
|
|
Term
| What G receptor do α2 adrenergic receptors stimulate? |
|
Definition
|
|
Term
| What G receptor do D1 & D5 DA receptors stimulate? |
|
Definition
|
|
Term
| What G receptor do D2, D3, & 4 DA receptors stimulate? |
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Definition
|
|
Term
| What G receptor do M1, M3, & M5 muscarinic acetylcholine receptors stimulate? |
|
Definition
|
|
Term
| What G receptor do M2 & M4 muscarinic acetylcholine receptors stimulate? |
|
Definition
|
|
Term
| What 2 neurotransmitters can function as fast neurotransmitters & slow neuromodulatory neurotransmitters? |
|
Definition
|
|
Term
| What 2 receptor types are stimulated by Glu? |
|
Definition
| ionotropic & metabotropic |
|
|
Term
| What 2 recptor types are stimulated by Ach? |
|
Definition
|
|
Term
|
Definition
| ligand gated ion channels at neuromuscular juntion |
|
|
Term
|
Definition
| G protein coupled receptors |
|
|
Term
| What are the 5 monoamine small molecule neurotransmitters? |
|
Definition
1) DA
2) Epi
3) NE
4) Serotonin
5) Histamine |
|
|
Term
| What are the 2 drug targets for monoamines? |
|
Definition
1) Vesicular storage
2) Reuptake/Catabolism |
|
|
Term
| How are catecholamines synthesized? |
|
Definition
Tyr => L-Dopa => DA => NE => Epi
(True Love Does Not Exist) |
|
|
Term
| What are the 4 enzymes needed in catecholamine synthesis? |
|
Definition
1) Tyrosine hydroxylase
2) Decarboxylase
3) DA β Hydroxylase
4) PNMT |
|
|
Term
| What do many psychoactive drugs taret? |
|
Definition
| G protein coupled receptors directly |
|
|
Term
| Where do sympathetic preganglionic neurons arise from? |
|
Definition
| thoracic & lumbar segments of the SC |
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|
Term
| Where do sympathetic preganglionic neurons project to? |
|
Definition
| postganglionic neurons in ganglia near the SC |
|
|
Term
| Where do the parasympathetic ganglia generally lie? |
|
Definition
| close to organs they innervate |
|
|
Term
| Where do parasympathetic preganglionic neurons arise from? |
|
Definition
| nuclei in the branstem & sacral segments of SC |
|
|
Term
| Are parasympathetic preganglionic generally long or short? |
|
Definition
|
|
Term
| Do parasympathetics generally project onto long or short postganglionic neurons? |
|
Definition
|
|
Term
| What are the primary neurotransmitters of DRG? |
|
Definition
| Glu, substance P, peptides |
|
|
Term
| What are the primary neurotransmitters of somatic motor neurons? |
|
Definition
|
|
Term
| What are the primary neurotransmitters of the preganglionic neuron? |
|
Definition
|
|
Term
| What are the primary neurotransmitters of the postganglionic neuron? |
|
Definition
|
|
Term
| What are the 3 major organizational motifs of the CNS cellular organization? |
|
Definition
1) Long-tract neurons
2) Local circuit neurons
3) Single-source divergent neurons |
|
|
Term
Function
Long-tract neurons |
|
Definition
| act as relay b/w periphery & higher CNS |
|
|
Term
| Where do long-tract neurons recieve their signal from? |
|
Definition
| convergent signals from many different neurons |
|
|
Term
| Where do long-tract neurons synapse? |
|
Definition
| divergent signal on many downstream neurons |
|
|
Term
Function
Local circuit neurons |
|
Definition
|
|
Term
| What is the local ciruit neuronal structure? |
|
Definition
| complex, arranged in layers, with inhibitory & excitatory neurons |
|
|
Term
Function
Single source divergent neurons |
|
Definition
| innervate thousands of neurons (usually in cerebral cortex) |
|
|
Term
| Where do signle-source neurons typically originate from? |
|
Definition
|
|
Term
| Where do dopaminergic single source divergent neurons arise from? |
|
Definition
| substantia nigra & ventral tegmental area |
|
|
Term
| Where do dopaminergic single source divergent neurons project to? |
|
Definition
Substantia Nigra => Striatum
Ventral Tegmental Area => cerebral cortex |
|
|
Term
Function
dopaminergic single source divergent neurons |
|
Definition
| initiation of movement & brain reward pathway |
|
|
Term
| Where do cholinergic single source divergent neurons arise from? |
|
Definition
| nucleus basalis, peduculopontine nucleus, & medial septal nuclei |
|
|
Term
| Where do cholinergic single source divergent neurons project to? |
|
Definition
| widely throughout the brain |
|
|
Term
Function
cholinergic single source divergent neurons |
|
Definition
| maintain sleep-wake cycle & regulate sensory transmission |
|
|
Term
| Where do noradrenergic single source divergent neurons arise from? |
|
Definition
|
|
Term
| What do the noradrenergic single source divergent neurons innervate? |
|
Definition
|
|
Term
Function
noradrenergic single source divergent neurons |
|
Definition
|
|
Term
| Where do serotonergic single source divergent neurons arise from? |
|
Definition
|
|
Term
| Where do serotonergic single source divergent neurons project to? |
|
Definition
| diencephalon, basal ganglia, and via the basal forebrain to the cerebral hemispheres, cerebellum, & SC |
|
|
Term
Function
serotonergic single source divergent neurons |
|
Definition
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