Communications Between Neurons Flashcards
Neurotransmitter
Chemical that is released by a terminal button
Synaptic transmission
Transmission of messages from one neuron to another through the synapse
Dendritic spine
Small bud on the surface of a dendrite with which a terminal bouton of another neuron forms a synapse
Synaptic cleft
Space between presynaptic and postsynaptic membranes
Location on a receptor protein to which a ligand binds
Binding site
Chemical that binds with the binding site of a receptor
Ligand
Structures that contain molecules of a neurotransmitter
Synaptic vesicles
Two mechanisms of transmitter binding
Ligand-gated ion channels
G-protein couples receptors
Ion channel that opens when a molecule of a neurotransmitter binds with a postsynaptic receptor
Neurotransmitter dependent
Receptor molecule in postsynaptic membrane of a synapse that contains a binding site for a neurotransmitter
Postsynaptic receptor
Receptor that contains a binding site for a neurotransmitter and an ion channel
Ionotropic
Alterations in the membrane potential of a postsynaptic neuron produced by release of neurotransmitter at the synapse
Postsynaptic potential
Three methods known to terminate transmission
Diffusion
Cleaving
Reuptake
Diffusion
Seeps out into extra cellular space
Cleaving
Tears apart through enzyme activity
Reuptake
Re-entry of transmitter back into the presynaptic neuron through activity of neurotransmitter transporters
Destruction of a neurotransmitter by enzyme after it’s release
Enzymatic deactivation
Hebb Rule
If a synapse repeatedly becomes active at about the same time that the postsynaptic neuron fires changes will take place in the structure or chemistry of the synapse that will strengthen it
Commonalities between LTP and memory
A brief experience produces a lasting effect
Repeated stimulation makes more LTP
Drugs that block or enhance LTP typically have the same effect on memory
Conditions which impair memory also impair LTP
Three different forms of glutamate receptors
NMDAR
AMPAR
Kinate
Neurobiology of LTP
Transmission of glutamate from presynaptic terminal bouton to postsynaptic dendritic spine
Basic sequence of events in the induction of LTP
Transmitter release
Binding to AMPAR
Postsynaptic depolarization
Increase in intracellular Ca+2 followed by structural changes
Calcium flow into a cell is controlled by which receptor being activated?
NMDA
NMDAR channel is blocked by
Mg ion
Removing the Mg ion requires two events
Glutamate has to bind to the NMDAR
The membrane has to depolarize
LTP long term potentiation
When two neurons fire at the same time repeatedly, synapses between them get stronger (fire together, wire together)
LTD long term depression
When two neurons fire out of sync, synapse between them get weaker (out of sync, lose link)
Two important types of neural plasticity
LTP
LTD
(Insertion of AMPAR)
Neural plasticity is required for
Learning and memory
NMDAR is important for
The induction of LTP but not expression
NMDAR is needed for what kind of memory?
Long term
