Neurotransmitters Flashcards
(38 cards)
List 3 common neurotransmitters and state if excitatory or inhibitory? (3)
Acetylcholine (Ach)- excitatory in skeletal
- inhibitory in heart
Glutamate (GLU)- excitatory
GABA- inhibitory
What are neuromodulators?
Examples? (3)
Cause change in synaptic membrane
Longer lasting- slower events- i.e. learning, development
Dopamine (DA)
Noradrenaline (NA)
Serotonin
How do local anesthetic work?
Examples?
Procaine and lignocaine
Interrupting axonal neurotransmission
Block sodium channels- prevent depolarisation
Nociception cannot be transmitted
How do local anaesthetic worj?
Diffuse through mucus membranes
Can act on muscle
What are two types of neurotransmitter receptors?
Ligand-activated (ionotropic)
Metabotropic
What is ionotropic receptor (ligand activated)?
Ion channel proteins
Excitatory or inhib
Open due ligand binding
How do ionotropic receptors/ligand activated ion channels work?
1) Open directly response to ligand binding
2) Undergo change shape when neurotransmitter binds
3) Allow ion influx/efflux from cell
4) Produce quick response
What receptor causes quick response?
Ionotropic/ligand activated ion channels
What are metabotropic receptors?
Trigger signal pathways- not ion channels
Excitatory or inhibitory
How does metabotropic receptors work?
Can indirectly affect ion channel open/close
Tend involve second messenger
Slow
What is main inhibitory neurotransmitter?
GABA
What is main excitatory neurotransmitter?
Glutamate
Where can Ach act? (3)
PNS- neuromuscular junctions
Brain and spinal cord
What are neurons called release Ach?
Cholinergic neurons
What do cholinergic neurons release?
Ach
What breaks down Ach? Into?
Acetylcholinesterase
Breaks Ach into choline and acetate
What breaks down Ach?
Were is choline transported after broken down?
Acetylcholinesterase
Choline transported back to presynaptic axon terminal
Choline reused
What are two types Ach receptor?
Nicotinic
Muscarinic
What do nicotinic receptors respond to? (2)
Where is found?
Respond Ach and nicotine
Found NMJ
How do nicotinic receptors work?
1) Ach causes ion channels open
2) Depolarisation target cell
What function are nicotinic receptors important in?
Cognitive function and behaviour
What are muscarinic receptors?
Location?
Couple with G proteins
Brain
PNS innervates peripheral glands/organs- salivary gland
Not ion channel
Trigger signal pathways- inhibit ap
What receptors used with G proteins?
Muscarinic
What receptors used with ion channels?
Nicotinic
