substrates

Question 1

what are the 4 catecholamines

Answer 1

• dopamine
• noradrenaline
• serotonin
• acetylcholine

Question 2

what are catecholamines

Answer 2

neurotransmitters and hormones derived from the amino acid tyrosine
- they play a key role in the body’s stress response, regulation of blood pressure, heart rate and various metabolic processes

Question 3

what does cocaine do to neurotransmitters

Answer 3

• inhibits DA and NA transporters

Question 4

what does amphetamines do to neurotransmitters

Answer 4

increased DA and NA release

Question 5

what does risperidone do to neurotransmitters

Answer 5

blocks DA receptors

Question 6

what does Ritalin do to neurotransmitters

Answer 6

blocks DA and NA uptake

Question 7

what is Reserpine and what does it do

Answer 7

• general catecholamine antagonist
• inhibits VMAT - a protein responsible for moving them back into vesicles

Question 8

what did Bloomfield et al 2016 and Reigal ate al 2007 find about indirect antagonists

Answer 8

THC promotes DA release through cannabinoid receptors
- long term DA system dulling

Question 9

what are dopamine pathways

Answer 9

neural circuits through which dopamine travels to regulate various physical and psychological functions
- these pathways are critical for processes like movement, reward, motivation, emotion and hormonal control

Question 10

what are the four dopamine pathways

Answer 10

• mesocortical
• mesolimbic
• nigrostriatal
• tuberoinfundibular

Question 11

where does the mesocortical originate

Answer 11

in the ventral tegmental area but projects to the prefrontal cortex

Question 11

what does mesocortical do

Answer 11

regulates cognition, decision making, emotion and social behaviour

Question 12

what is underactivity in the mesocortical pathway associated with

Answer 12

negative symptoms of schizophrenia and cognitive impairments

Question 13

what do drugs that target the mesocortical pathway aim to do

Answer 13

aim to modulate dopamine activity in the prefrontal cortex

Question 14

what do mesocortical drugs address

Answer 14

• cognitive dysfunction, emotional regulation, and negative systems in disorders like schizophrenia, ADHD and depression

Question 15

what is the function of the mesolimbic dopamine pathway

Answer 15

involved in reward, motivation and the feeling of pleasure

Question 16

where does the mesolimbic pathway originate

Answer 16

in the ventral tegmental area and projects to the nucleus accumbens and other limbic areas

Question 17

what does overactivity in the mesolimbic pathway do

Answer 17

linked to addiction, positive symptoms of schizophrenia and other disorders involving reward processing

Question 18

what do drugs that target the mesolimbic pathway aim to do

Answer 18

modulate the dopamine activity in the reward and motivation system of the brain

Question 19

what are mesolimbic drugs used to treat

Answer 19

• schizophrenia
• addiction
• depression
• parkinson’s disease

Question 20

what does high dopamine in the mesolimbic pathway result in

Answer 20

psychosis, addiction, mania

Question 21

what does low dopamine in the mesolimbic pathway result in

Answer 21

depression, anhedonia, apathy

Question 22

what does the dopamine pathway nigrostriatal do

Answer 22

controls movement and motor planning by facilitating the interaction between the basal ganglia and other motor control systems

Question 23

where does nigrostriatal pathway originate

Answer 23

starts in the substania nigra and projects to the striatum

Question 24

what happens if there is degeneration of neurons in the nigrostriatal pathway

Answer 24

- a hallmark of parkinson's disease, leading to tremors, rigidity, and bradykinesia

Question 25

what happens if there is overactivity in the nigrostriatal pathway

Answer 25

- involuntary movements like tardive dyskinesia

Question 26

what are nigrostriatal drugs crucial for

Answer 26

motor control

Question 27

what are nigrostriatal drugs used for

Answer 27

parkinson's disease, drug-induced movement disorders, and Huntington's disease

Question 28

what does low dopamine in the nigrostriatal pathway do

Answer 28

leads to parkinson's disease

Question 29

what does excess dopamine in the nigrostriatal pathway do

Answer 29

leads to tardive dyskinesia and huntington's chorea

Question 30

what does the dopamine pathway tuberoinfundibular do

Answer 30

regulates the secretion of prolactin from the anterior pituitary gland, playing a role in hormonal control

Question 31

where does the tuberoinfundibular pathway originate

Answer 31

the hypothalamus and projects to the pituitary gland

Question 32

what can dysfunction in the tuberoinfundibular pathway do

Answer 32

can result in hyperprolactinemia, leading to symptoms such as infertility, sexual dysfunction and galactorrhea

Question 33

what does dopamine act as in tuberoinfundibular drugs

Answer 33

a prolactin antagonist

Question 34

what does decreased prolactin in the tuberoinfundibular pathway lead to

Answer 34

hypopituitarism

Question 35

what does increased prolactin in the tuberoinfundibular do

Answer 35

lead to infertility, menstrual irregularities, decreased libido, and galactorrhoea

Question 36

what receptors does DA have

Answer 36

- D1-like (D1, D5) - D2 - like (D2, D3, D4)

Question 37

which DA receptor activates easily

Answer 37

D3

Question 38

which DA receptor is not activated easily

Answer 38

D1

Question 39

which DA receptor excites the neuron

Answer 39

D1-like

Question 40

which DA receptor calms down the neuron

Answer 40

D2-like

Question 41

what did Giros et al 1996 find

Answer 41

an animal under treatment to become more hyperactive will respond by wanting more of that treatment, suggesting it's rewarding and showing addicting potential

Question 42

what did Xu, Guo, Vorhees and Zhang 2000 find

Answer 42

mutant mice lacking D1 receptors are insensitive to cocaine which increased locomotor activity in the wild-type but not the knockout mice