3.2 Neurotransmitter system

Question 1

What are the three major groups of chemical mediators

Answer 1

-Classical neurotransmitters= molecules that are made to be synthesised and stored in nerve terminals and are essential for the responsibility for transmitting a signal across the synaptic gap

-Neuromodulators = role in CNS function , they change the sensitivity of individual sign that perhaps to any neurotransmitter substance (Role is plasticity the connect are made and broken constantly)

-Neurotrophins= growth factors specialised growth factors that are targeted towards cells in the CNS they determine the neuronal survival

Question 2

1.What are examples of ‘small molecule neurotransmitters
2.Their molecular target
3. Role

Answer 2

1.Ach, Glutamate,Dopamine,

2.Ligand gated ion channels, GPCRs

3.fast / slow’ synaptic transmission

Question 3

1.What are examples of Neuropeptides
2.Their molecular target
3. Role

Answer 3

1.Endorphins,substance P
2.GPCRs
3.Neuromodulation

Question 4

1.What are examples of Neuromodulators
2.Their molecular target
3. Role

Answer 4

1.Nitric oxide
2.Guanylate cyclase
3.Neuromodulation /synaptic plasticity

Question 5

1.What are examples of Neurotrophins
2.Their molecular target
3. Role

Answer 5

1.Nerve GrowthFactor, BDNF, IL-1
2.Kinase-linked receptors
3.Neuronal growth,survival and plasticity

Question 6

1.What is dopamine
2.What is the Dopamiergnic pathway

Answer 6

1. Dopamine is a monoamine neurotransmitter and catecholamine
2. AA tyrosine converts to L-Dopa then that is decarboxylated to form Dopamine

Question 7

What areas of the brain are Dopamine highly concentrated?

Answer 7

• Substantial nigra
• Ventral Tegmental Area
• Hypothalamus
• Olfactory bulb
• Retina

Question 8

What are the different Dopamine pathways?

Answer 8

-Mesostraital pathway= from substance nigra to striatum

-Mesolimbic pathway= from ventral tegumental area to accubens nucleus

• ,Mesocortiyal pathway- ventral tegmental area to cerebral cortex

Question 9

What is the role of the pathway?

Answer 9

To get Dopamine from high concentrated area to other area of the brain

Question 10

1.What does Dopamine act on?
2.How is Dopamine removed from the synaptic cleft?

Answer 10

1. Acts on G protein receptors
2. Dopamine transporter

Question 11

What is GABA and what is it’s function?

Answer 11

1.GABA is a neurotransmitter and it function changes over the course of neural development

Question 12

What is the GABAergic pathway?

Answer 12

Has a structure of AA that is synthesised from another neurotransmitter Glutamate and it is catalysed by the enzyme glutamic acid decarboxylase

Question 13

1. What are the two GABA receptors?
2. What is the function of the two GABA receptors?

Answer 13

1. GABA A and GABA B
2. GABA A is inotropic when GABA binds to it it opens the ion channel allowing cl- in the channel causing hyper polarisation (No neurons firing off AP)

GABA B is metabotropic GABA binds to it can allows K+ ions to flow out the ion channel causing hyper polarisation so less likely of the neurons firing off AP/

Question 14

How is GABA actions determined?

Answer 14

GABA transporters

Question 15

What can increase in GABA activity cause?

Answer 15

Sedative effects
e.g Alcohol and benzodiazepine

Question 16

What are the functions dopaminergic pathway?

Answer 16

• Motivation & reward =Drug dependency
  -Voluntary movement= Parkinson’s Disease- -Cognition= ADHD
  -Affect (how you feel) =Schizophrenia

Question 17

What are the 5 dopamine receptors?

Answer 17

D1 D2 D3 D4 D5

Question 18

what are the functions of GABAergic pathway?

Answer 18

-Fast’ cortical signalling =Epilepsy
-Cognition =Sedation
-Memory= Amnesia
-Voluntary movement =PD, Huntington’s Disease

Question 19

What GABA third receptor that is not known to all?

Answer 19

GABA p