Unit 1 - 5 Flashcards
Soups vs Sparks experiment
Collecting fluid from around a slowed heartbeat and applying it to the fluid to a second heart (figuring out synapse is chemical, not electrical)
Synaptic transmission step 1
Electrical signal of AP reaches axon terminal
Synaptic transmission step 2
Depolarization of that wave of positive charge opens calcium channels
Synaptic transmission step 3
Influx of calcium ions triggers vestibule fusion with neuronal membrane. Dumps NTs in cleft
Synaptic transmission step 4
NTs bind to receptors on postsynaptic membrane. Opens ion Channels creating an EPSP or IPSP, turns signal back to electrical
Synaptic transmission step 5
EPSP/ IPSP spreads through dendrite and soma towards axon hillock.
If membrane potential reaches threshold, postsynaptic neuron fire own AP (starting new process)
Synaptic transmission step 6
In synaptic cleft, NTs is cleared so transmittion stops
Synaptic vesicles come from
Endomembrane system, Golgi apparatus
Neurotransmitters come from
Enzyme made by protein at synthesis in soma
NT Receptor Structure (5)
- Extracellular side = cleft
- Intracellular side = postsynaptic cell
- Ligand binding site -where ligands bind
- ligands - molecules that bind to receptor
- Ion channels
Agonist
Ligand that activates receptor
Antagonist
Ligand that inhibits receptor
Ionotropic receptor
Contain ion channels which open in response to NT binding
Metabotropic receptor
don’t contain channels themselves but cause separate membrane channels to open
How does transmission stop? (3)
Reuptake, degradation of transmitter by enzymes, receptor inactivation (ligands leave binding sites)
NTs are made of (4)
- Amino acids (protein building blocks)
- Peptides (amino acid chains)
- Amines (modified amino acids)
4: gases
Major NTs (7)
- Glutamate
- GABA
- Acetylcholine
- Dopamine
- Serotonin
- Norepinephrine
- Opioids
Glutamate
Major Excitatory nt, receptors = AMPA and NMDA, important in memory function
GABA
Major inhibitory nt, GABAa = ionotropic receptors, respond to benzodiazepines, GABAb = metbotropic receptors, target for pain and mood disorders
Acetylcholine
Neuromuscular junction, primary nt. Important in learning and memory
Dopamine
Critical role in motor control, feelings of reward and pleasure, important for learning w/ positive reward
Serotonin
Mood, vision, sexual behavior, anxiety, sleep
Norepinephrine (noradrenaline)
Nt and hormone, Alertness, mood, sexual behavior
Opioid
Enkephalin and endorphins, Analgesic (painkilling) properties, reward functions
Gases
NO and CO, don’t have receptors, diffuse across membranes, retrograde (go backwards)
