Intro to Nervous System Flashcards
What are three types of neurotransmitters?
1-Inhibitory (GABA)
2-Excitatory (Glutamate)
3-Both (Acetylcholine or Serotonin)
What are the two was neurotransmitters interact?
1-Direct Action (binds and opens-rapid response)
2-Indirect Action (second messengers, G proteins-Longer lasting/slow onset)
What are the two types of membrane channels?
1-Voltage gated (opens in response to voltage)
2-Ligan-gated/ionotropic (binding of ligand opens)
What type of channels are not directly linked to ion channels, initiate biochemical processes and modify responsiveness of the neuron?
Metabotropic
What are the two types of metabotropic receptors?
1) Membrane-delimited
2) Diffusible second messengers
A receptor on an axon terminal that is affected by a neurotransmitter produced by the same cell is called?
Autoreceptor
*D2 receptor with dopamine is an example
A receptor on an axon terminal that is affected by a neurotransmitter from another neuronal cell type is called?
Heteroreceptor
*Like Dopamine acting on a serotonin neuron
What are the 3 main catecholamines?
1-Dopamine
2-Norepinephrine
3-Epinephrine
What amino acid is the precursor for dopamine?
Tyrosine
Which enzyme converts tyrosine to dopa?
Tyrosine hydroxylase
Dopa is converted by what to make Dopamine?
Aromatic Amino Acid decarboxylase (AADC)
Which transporter takes up dopamine, serotonin, norepinephrine and epinephrine into vesicles?
Vesicular Monoamine Transporter (VMAT)
Which auto receptor binds dopamine?
D2
*decreases dopamine release and tyrosine hydroxylase activity
Which enzyme metabolizes Serotonin, dopamine, and norepinephrine/epinephrine?
Monoamine oxidase
Which enzyme converts DA to Norepinephrine?
Dopamine Beta Hydroxyslase
What two kinds of receptors does NE bind to post synaptically?
Alpha and Beta receptors
Which auto receptor is bound by NE?
Alpha 2
Which enzyme catalyzed the conversion of Norepinephrine to Epinephrine?
Phenylethanolamine-N-methyltransferase (PNMT)
T or F, Serotonin is a catecholamine?
FALSE
What is the amino acid precursor for Serotonin?
Tryptophan
Which enzyme converts Trytophan to 5 Hydroxy tryptophan?
Tryptophan Hydroxylase
Which enzyme converts 5 Hydroxy tryptophan to 5 Hydroxy tryptam ine (serotonin)?
Amino Acid Decarboxylase (AADC)
What is the precursor for Acetylcholine?
Choline
What combines with choline to be converted to acetylcholine by choline acetyl transferase?
Acetyl CoA
What Metabolizes acetylcholine outside of the neuron?
Acetylcholinesterase
What type of presynaptic receptor does acetylcholine act on?
Muscarinic receptor
*This is an autoreceptor
What are two important Amino Acid neurotransmitters?
- GABA (Inhibitory)
- Glutamate (Excitatory)
What is the precursor for Glutamate that is converted by amino transferase?
Alpha Keto-Glutarate
What are the 3 post synaptic receptors that Glutamate binds after being released?
1-NMDA
2-AMPA
3-Kainate
As part of Glutamate regulation, what enzyme converts it to Glutamine in astrocytes?
Glutamine Synthetase
Which enzyme converts Glutamine from astrocyte cells back to glutamate in neurons?
Glutaminase
Which enzyme converts Glutamate to GABA?
Glutamate decarboxylase (GAD)
*GABA=Gamma aminobutyric acid
What is GABA degraded to in astrocytes?
Succinate
What are two post synaptic receptors that GABA binds?
1-GABA-A
2-GABA-B
What three things do most neurotransmitters do?
1-Bind post synaptic receptors
2-Bind Autoreceptors
3-Be taken up again to be metabolized or used again
What are 5 other substances that act on the brain?
1-Histamine 2-Endorphins 3-Neuropeptides 4-Endocannabinoids 5-Nitric Oxide
Which receptor does Histamine act on?
H3
*functions as an inhibitory heteroreceptor
What do endorphins acting on u opiod receptors do?
Activated opiate receptor lead to decrease GABA release
*Less GABA release results in increase Dopamine release
What are the two main things Nitric Oxide does?
1-Gaseous signaling molecule
2-Relax vascular smooth muscle
*CNS role may be controversial
What protein transports Glutamate into vesicles?
Glutamate transporter
