Fundamentals of Neuroscience Exam 2

Acetylcholine: Group

on its own

Acetylcholine: Precursor

acetyl and choline

Acetylcholine: Enzyme construction

choline acetyltransferase

Acetylcholine: What move it into vesicles

Vesicular acetylcholine transporter

Acetylcholine: What inactivates it

Acetylcholinesterase

Acetylcholine: Receptors

Nicotinic, Musanaric

Acetylcholine: Associated Diseases

Myasthenia gravis, Alzheimers

Epinephrine: Group

Catecholamine

Epinephrine: Precursor

Norepinephrine

Epinephrine: Brain area of origin

Medullary Epinephrine neurons

Norepinephrine: Group

Catecholamine

Norepinephrine: Precursor

Dopamine

Norepinephrine: Associated Diseases

Depression

Norepinephrine: Brain Area of origin

Locus Coeruleus

Dopamine: Group

Catecholamine

Dopamine: Precursor

DOPA

Dopamine: Enzyme Construction

DOPA decarboxylase

Dopamine: What moves it into vesicles

VMAT

Dopamine: Inactivation

DAT (Dopamine transporter)

Dopamine: Associated diseases

Parkinson’s and schizophrenia

Dopamine: Brain area of origin

Substantia nigra and ventral tegmental area

Serotonin: Group

Catecholamine

Serotonin: Precursor

Tryptophan

Serotonin: Enzyme construction

Tryptophan 5 Hydroxylase

Serotonin: What moves it into vesicles

SERT (Specific serotonin transporter)

Serotonin: Associated diseases

Depression

Serotonin: Brain area of origin

Raphe nuclei

Glycine: Group

Amino Acid

Glycine: Precursor

Serine

Glycine: Enzyme construction

serine hydroxymethyl-transferase

Glycine: What moves it into vesicles

VIAAT

Glycine: Inactivation

Glycine transporters

Glycine: Receptors

Ionotropic chloride channels

GABA: Group

amino acid

GABA: Precursor

Glutamate

GABA: Enzyme construction

Glutamic Acid Decarboxylase (GAD)

GABA: What moves it into vesicles

VIAAT (Vesicular inhibitory amino acid transporter)

GABA: Inactivation

GAT (glutamate transporters)

Glutamate: Group

amino Acid

Glutamate: Precursor

Glutamine

Glutamate: Enzyme construction

glutaminase

Glutamate: What moves it into vesicles

VGLUT (Vesicular glutamate transporter)

Glutamate: Inactivation

EAAT (Excitatory amino acid transporter)

Glutamate: Receptors

AMPA, NMDA

GPCR: Is activation of this step amplifying?

No, the neurotransmitter is staying bound to the receptor.

GPCR: What initiates or activates this signaling step?

Neurotransmitter or ligand binds to receptor

GPCR: What inactivates this step?

Ligand leaves the receptor

GPCR: Where is this step located?

The cell membrane (Both sides)

G-Protien: Specific Gs Pathway Component

Heterotrimeric G-Protien

G-Protien: Is activation of this step amplifying?

Yes

G-Protien: What activates this step?

G-protein binds to activated receptor, causing a shape change that makes the alpha subunit replace GDP with GTP

G-Protien What inactivates this step?

G-protien alpha subunit is inactivated with GTP, is subbed out for GDP, causing all three subunits to come back together

G-protien: Where is this step located?

Inside of the cell membrane

Effector: Specific Gs pathway component

Adenylyl cyclase

Effector (Adenylyl cyclase) - Is activation of this step amplifying?

No, one G-protien alpha subunit needs to stay in place to keep it active

Effector(Adenylyl cyclase) : What activates this signaling step?

G-protein alpha subunit binds and stays bound to keep AC activated

Effector(Adenylyl cyclase) : What inactivates this step?

G-protein alpha subunit leaving adenylyl cyclase

Effector(Adenylyl cyclase) : Where is this step located

Inside of the cell membrane

Second Messenger: Specific Gs Pathway Component

Cyclic AMP (cAMP)

Second Messenger(cAMP): Is activation of this step amplifying?

Yes, adenylyl cyclase can produce a lot of cAMP

Second Messenger(cAMP): what activates this step?

Activated adenylyl cyclase produces cAMP from ATP

Second Messenger(cAMP): What Inactivates this step?

cAMP is degraded by cAMP phosphodiesterase

Second messenger(cAMP): Where is this step located?

cAMP Spread throughout the inside of the cell

Protein Kinase: Specific Gs Pathway Component

Protein Kinase A (PKA)

Protein Kinase (PKA): Is activation of this step amplifying?

No, two cAMP must bind and stay bound to each regulatory subunit (4 cAMP total)

Protein Kinase(PKA): What initiates or activates this step?

Two cAMP bind to each regulatory subunit of PKA, freeing the catalytic subunits and allowing them to phosphorylate

Protein Kinase(PKA): What inactivates this step?

When cAMP leaves the regulatory subunits the catalytic subunits become bound again

Protein Kinase(PKA): Where is this step located?

Spread all throughout the inside of the cell

Phosphorylation Target: Specific Gs Pathway Component

cAMP response element binding protein (CREB)

Phosphorylation Target(CREB): Is activation of this step amplifying?

Yes, a single PKA can phosphorylate many CREB proteins

Phosphorylation Target(CREB): What activates this step?

CREB is activated when it is phosphorylated by PKA (Has a phosphate group attached to it)

Phosphorylation Target(CREB): What inactivates this step?

CREB becomes inactivated when it is de-phosphorylated by a protein phosphatase

Phosphorylation Target(CREB): Where is this step located?

In the nucleus

Presynaptic

axon terminal- sending neurotransmitter

synthesis and storage, release

Postsynaptic

dendrites (spine)— receiving neurotransmitter

activation of receptors

Synapse

structure where the presynaptic and postsynaptic neurons meet and NT is released

Synthesis and storage

Stage one,

a. small molecule NT are produced in the axon terminal and then are loaded into vesicles

b. peptide NT are produced in the cell body through transcription and translation

Presynaptic

Release into the synaptic cleft

Stage 2,

• we need an influx of calcium in order to release presynaptic neurotransmitter

Presynaptic

SNAREs

proteins involved in releasing NT by making vesicles fuse to the cell membrane

Synaptotagmin

the thing that calcium binds to which causes the vesicle to fuse with the cell membrane and release NT

• calcium is moving inside the cell to release NT

Ionotropic receptors

ligand gated ion channels

metabotropic receptors

initiate intracellular signaling

What are the 4 ways neurotransmitters are inactivated quickly?

1. Diffusion from synapse

2. Enzymatic activation

3. Neuronal Reuptake

4. Glial cell cleanup

How do we study ionotropic receptors?

with end plate currents

What are nicotinic acetylcholine receptors permeable to?

Both Na+ and K+

Postsynaptic potential

the potential caused by the movement of ions through ionotropic receptors

Excitatory Postsynaptic Potentials (EPSPs)

make the cell more likely to fire an action potential

reversal potential above the cells threshold potential

Inhibitory Postsynaptic Potentials (IPSPs)

makes the cell less likely to fire an action potential

reversal potential below the cells threshold potential

Spatial summation

two PSPs that are produced close to each other summate

Temporal summation

two PSPs that are produced at the same time summate

What is Protein Kinase A made out of

regulatory and catalytic subunits

Is glutamate excitatory or inhibitory?

excitatory

Are GABA and glycine excitatory or inhibitory?

Inhibitory

The gill siphon withdrawal reflex

aplysia innate reflex to pull their gil into their bodies when the siphon (or tail) is touched

Habituation

when a behavioral response becomes less and less with repeated instances of non-aversive stimulus

Why does it matter that habituation causes less calcium in the cell?

less calcium influx = less NT release = less motor neuron excitation = less muscle response

how is the synapse affected by habituation and sensitization?

habituation = weakened synapse

sensitization = stronger synapse

Are the mechanisms for habituation and sensitization presynaptic or postsynaptic?

presynaptic

Sensitization

when a painful stimulus causes a much stronger response in the future

*Serotonin, Phosphorylating K+ channels

Long term sensitization

enough cAMP that so much protein kinase A is activated, it’s going to move into the nucleus and activate CREB, which will transcribe genes