Synaptic Transmission Flashcards
What are the classification of neurons?
Unipolar Neuron- Single elongates process with cell body located off to the side
Bipolar Neuron- Two processes separated by the cell body
Multipolar neuron- More than two processes , a single axon. and multiple dendrites
Give an example of Demyelinating neuropathies, symptoms and cause?
Multiple Sclerosis
Weakness and paralysis
Reduced conduction velocity
There are negative and positive symptoms
It can be caused by genetic diseases, metabolic disorders, intoxication, nutritional disorders, carcinomas and immunological disorders
( Effected one has the fibre exposed and Myelin sheath is breaking off /damaged)
1.What is Tetrodotoxin?
2. Where is it found?
3.What does it do?
- Tetrodotoxin is a potent posion (Neurotoxin)
- Found in Puffer fish which are normally located in Japan
- It inhibits Sodium channels causing death in seconds
What is a synapse and what are the 2 types?
Synapse is the gap between the presynaptic and postsynaptic (Connection happens)
2 Types- Chemical and Electrical (less common one)
Where are microglia from?
Where do they do
What is their structure?
1.Derived from bone marrow
2.Change morphology in response to injury
3.Double-edged sword
What are Ependymal cells
Where are they located
What their functions?
- Single layer of ciliated cuboidal cells
2.Line the ventricles of the brain
3.Produce and circulate cerebrospinal fluid
What are the main neurotransmitters and where do they come from
-Dopamine, adrenaline and noradrenaline –EAA TYROSINE
-Serotonin – EAA Tryptophan
-Glutamate and GABA-Glutamine
What are neurotransmitters and what can they bind to?
- Neurotransmitters are chemical produced and released by neurone they can be excitatory or inhibitory
They can bind to muscles, tissues, cells and glands
What does ACH do in PNS and CNS?
PNS- Skeletal muscle contraction via musranic receptor
CNS- memory cognition
What are the excitatory and inhibitory in Aderadeline and dopamine
Aderadeline - Alpha1 and Beta 1 = excitatory Alpha 2 and Beta 2 = inhibitory
Dopamine- DA1= Excitatory DA2= Inhibitory
What are the excitatory and inhibitory in serotonin (5-HT) and GABA
Serotonin- 5HT1+5= Inhibitory 5TH2,3,4,6,7= Excitatory CNS=sleep PNS= GIT
GABA- GABA A and GABAB inhibits neutrons from firing off
What are the receptors for Glutamate
NMDA and AMPA used for neurons firing off
How is transmission terminated
*Reuptake- Dopamine and serotonin
* Enzymatic degradation- Ach
* Diffusion- Glutamate
What are the steps of Synaptic transmission
1.
Synthesis of the neurotransmitter in the presynaptic nerve terminal.
2.
Storage of the neurotransmitter in secretory vesicles.
3.
Regulated release of neurotransmitter in the synaptic space between the pre- and post-synaptic neurons.
4.
The presence of specific receptors for the neurotransmitter on the postsynaptic membrane, such that application of the neurotransmitter to the synapse mimics the effects of nerve stimulation.
5.
A means for termination of the action of the released neurotransmitter.
What happens in repolarisation?
1.Repolarisation is positive charge going back to negative or even more negative which is hyper-polarisation
- 30mv activates the K+ channels allowing it leave the cell so it has higher concentration outside and the voltage goes from 30mv to -90mv
- 30mv activate the second K+ channels then it voltage goes to -90mv which inhibits the ca+ channel so no ca+ will fuse/ be released to the post synaptic cleft
