cell communication Flashcards
what is the nervous system designed to carry ?
information rapidly and efficiently
what is the key of communication
To detect changes and carry information to the CNS
To process the information
To decide and plan on appropriate response
To tell the body what do to
what does communication depend on ?
Interactions between neurons
Anatomical relationship between neurons
what happens once the action potential reaches the synapse ?
it needs to cross to the next cell
2 types of synapse which enable cell-cell communication
1.chemical synapse
2.electrical synapse
3 different types of connections
1.axo-dendritic
2.axo-somatic
3.axo-axonic
chemical synapse
Can cope with fast transmission rates
Ionotropic and metabotropic channels
Vesicles releases from presynaptic terminal
Act on receptors in postsynaptic terminal
Major drug target
Electrical
More effective with slower transmission rates Gap junctions
Small molecules and current
‘low-pass filter’
Synchrony
Up-and-coming drug target
what functions does chemical synapse have?
1.pre-synaptic terminal
2.vesicle
3.transmitter
4.receptor
what functions does electrical have?
1.gap junction
2.post-synpatic terminal
4 methods by which cellular communication occurs
1.excitation
2.inhibiton
3.disinhibition
4.lateral inhibition
how do neurones carry the message ?
action potential is a method of communication
what does the strength of the action potential be altered at?
level of the neuron or the network
when coding information , why is inhibition important?
inhibition of thecells shapes the pattern of action potentials to give it meaning.
when coding information what does excitation do?
the principal cell is important (providing the action potentials that are carried along
Direct inhibition
neurones generally, lack of pattern means nothing to the brain, but when the inhibitory neurons block some of the firing this gives rise to patterns that can contain information
disinhibition
plays a key role in the Basal Ganglia circuitry which shapes motor function
what does activation of inhibitory circuit lead to
excitation
Lateral inhibiton
Activation of excitatory cells also activates associated inhibitory cells
in lateral inhibition, what does inhibition act on?
neighbouring cells to reduce activity
in lateral inhibiton what does inhibition do to the response?
Strengthens response of cell directly stimulated
in lateral inhibition what are the sensory pathways?
-vision
-touch
-olfaction
what are the 3 ways you can improve the signal transmission?
1.myelination
2.plasticity
3.sychrony
how can Myelination improve signal transmission?
You can alter the speed of transmission along the axon
how can plasticity improve signal transmission?
You can alter the strength of the signal at the level of the network
what is myelination
Acts like Insulation on a wire:
Speeds communication
Allows Saltatory conduction
what 2 disorders associate with myelination
Multiple Sclerosis (CNS)
Guillain Barré (PNS)
Plasticity
describes the ability of a neuron to up- or down-regulate the strength of it’s synaptic connections
what are the 3 way that occurs in plasticity:
1.Synaptic morphology
2.Metabolic changes
3.Receptor changes
what the two models of plasticity
1.Long-term potentiation
2.Long-term depression
what does plasticity improve
improves synaptic transmission at the neuronal level
Synchrony
describes the co-ordinated firing of a number/network of cells
2 ways synchronous activated can be activated?
1.gap junctions
2.pacemaker cells
what do gap junctions and pacemaker cells help with?
allow network of cells to fire simultaneously
