NEUROTRANSMITTERS Flashcards
What makes a NT a NT : 5 rules for being a true chemical NT ?
- chemical must exist (made and stored) in presynaptic cells (stored in terminals)
- chemical must be released from presynaptic terminals on action potential
- Released chemical must bind to receptors and cause a biological effect
- must be a mechanism to inactivate or metabolise the chemical
- chemical should have same biological effect if artificially applied to synapse (e.g. by microinjection to brain area - exogenously applied)
Where do NT come from?
Peptides
Peptides (made in the soma)
* Precursor peptide (small protein) synthesised in rough ER
* Cleaved in Golgi apparatus to active neurotransmitter
* Secretory vesicles bud off from Golgi apparatus
* Secretory granules (large vesicles, 100 nm) transported to terminal and stored
Where are Monoamines, Amino Acids & Acetylcholine made?
PRE-Synaptic terminal
pre-synaptic terminal)
- Precursor molecule (from diet) synthesised to neurotransmitter
- Transported to synaptic vesicle (50 nm) and stored
*****Overview the synthesis and storage of NT?Diag p65
What is Main Difference between Peptides & Monoamines, Amino Acids or Acetylcholine neurotransmitters?
Made ?
Transported?
- Peptide neurotransmitters are made in the soma and transported in secretory granules to the terminal
- Monoamines, amino acids and acetylcholine are made from precursor molecules in the terminal and are transported into synaptic vesicles
Overview life of a NT?
Diag p 66
Name 7 NT?
A- A- M- P- L- N- S
Art, arty Mic picked lovely new sweets
Amino Acids
Acetylcholine
Monoamines/Trace Amines
Peptides (e.g., Substance P)
Lipids (e.g. Anandamide)
Nucleosides (e.g., ATP)
Soluble gases (e.g., Nitric Oxide: Viagra)
What are the major roles of Glutamate?
E-L-N-E
Excitatory NT
Learning and Memory
neuroplasticity
Excitotoxicity
What are the major roles of GABA
Inhib.
Inhibitory NT
Modulator of many processes
Role of Dopamine
Memory + 3 more
STM
Strategy / Planning
Reward
Movment
Serotonin..
C-E-R
Cogntion
Emotion
Reward
Noradrenaline..
Attn, F & F, ?
Attention
Sleep
Fight/ Flight
Acetylcholine
Memory + 3 more
Memory
Percpetual Learning
Movement
REM sleep
What are the 3 common amino acids ?
G G G
Glutamte
GABA
Glycine
diag.p 67
Amino acids: where are the cell bodies?
GABA: many found in interneurons
Diag p 68
Overview Amino acid synthesis? ( G-A G)
Glutamate, Aspartate, glycine: common Amino acids: used in protein syntheses, ( synthesised from glucose.
Diag. p69
Amino acid metabolism
see diagram p 70
What are acetylcholine celll bodies? ( Excitatory)
diagram p 71: ACh is predominantly excitatory ACH - taken up by ACh transporter into vesicles and stored
Describe acetylcholine metabolism ? ( AChE)
ACh is broken done by Acetylcholine esterase (AChE)
ACh metabolism occurs in synaptic cleft : Choline transported into presynaptic cell for re-use
- Insecticides or nerve gases inhibit AChE . Engaces ACh transom at ms/ art : death usu by respond.paralysis
- Diag p72
What are the categories of Monoamines? 3/2
3 catecholamines
2 Indolamines
What are the 3 Catecholamines?( D-N -A)
Dopamine
Noradreanlaine
Adrenaline : hormone from kidney ( adrenals)
What are the 2 Indolamines ? ( M+ S)
Serotonin
Melatonin ( Circadian Rythym
* histamine: wakefulness/ low level in blood : hypothalamus/ forebrain
Where are the dopamine and Noradrenaline cell bodies?
NOR: locus coeruleus and caudal raphe nuclei
Dopamine: sub nigra
ven. segmental area
mesolimbic system
nigostriatal system
monoamines: what is the synthesis process of catecholamines? (T-L- N- A)
Tyrosine >
L-DOPA>
Noradrenaline>
Adrenaline
diagnosis p 74
Where are serotonin cell bodies? ( raphe nuc.)
Rostral raphe nuclei
caudal raphe nuclei
Synthesis process of serotonin? ( trytophan)
Trptophan>
5- Hydroxytryptophan .
5- Hydroxytrypatmine
Trptophan is an amino acid: found in grains, meat and dairy
Overview metabolism of monoamines?
diagnosis p 76
What are Monoamines rebased? (D-N -S)
Dopamine is released from dopamine cells
Noradrenaline is released from noradrenaline cells
(if dopamine b hydroxylase is present in cell - the cell is noradrenergic)
Serotonin is released from serotonin cells
What are transporters of monoamine? ( D-N- S)
Dopamine = DAT
Noradrenaline = NET (due to US naming of norepinephrine) Serotonin = SERT
They are each taken up into their own cell and metabolised or repackaged into vesicles
Know the following!
- Know the 5 rules of defining a chemical neurotransmitter (slide 5)
- Know your amino acids, acetylcholine and monoamines
- Know WHERE they are made how they are metabolised (you do not need to know the chemical reaction for their synthesis (manufacture))
- Know where their cell bodies are
