Psycho-Neurochemistry

Question 1

process by which electrical signals (nerve impulse) are converted into chemical signals by presynaptic neuron

Answer 1

signal transduction

Question 2

postsynaptic neuron

Answer 2

convert chemical signals back into electrical signals

Question 3

receptors proteins (synaptic connection)

Answer 3

detect neurotransmitters receptors are made of proteins & are found in the pre & post synaptic neuronal membrane.

Question 4

detection of neurotransmitters

Answer 4

activation of postsynaptic neuron

Question 5

activation of postsynaptic neuron

Answer 5

causes membrane depolarisation (excitation ) or hyperpolarisation(Inhibition)

Question 6

type of synapses

Answer 6

chemical - use neurotransmitters
electrical - electric current & charged ions
conjoint - both chemical & electrical synapses

Question 7

synapses are either

Answer 7

excitatory or inhibitory

Question 8

excitatory synapses

Answer 8

induce membrane depolarisation (more positive)

Question 9

Inhibitory synapses

Answer 9

induce membrane hyperpolarization (more negative)

Question 10

types of neurotransmitters include

Answer 10

biogenic amines
amino acid
peptide acid (encephalins hormones endocannabinoids)

Question 11

biogenic amines

Answer 11

make up 5-10% of neuro messengers in CNS
Including:
1.Catecholamines (Dopamine, epinephrine & nor epinephrine)
2.Indole amines (serotonin-5HT)
3.Quaternary amines (acetylcholine)
4.Ethyl amines (histamine)

Question 12

amino acid

Answer 12

make up 60% of neuro messengers

Question 13

peptide acid

Answer 13

make up the rest of neuro messengers around 30%

include encephalins hormones and endocannabinoids

Question 14

encephalins

Answer 14

act on opiate receptors such as

• beta endorphins
• substance p
• vasopressin
• cholecystokinin (CCK)
• Neurotensin (NT)

Question 15

neurotransmitter hormone

Answer 15

• thyrotropin also called thyroliberin releasing hormone or factor (TRH)
• neuropeptide Y
• adrenocorticotropin hormone (ACTH)
• corticotropin releasing factor(CRF)
• rexins.

Question 16

types of receptors

Answer 16

• polypeptide chains receptors

- nicotnic acetylcholine receptors

Question 17

polypeptide chains receptors

Answer 17

• adrenergic
• D2 dopaminergic
• M1 muscarinic

Question 18

nicotinic acetylcholine receptors

Answer 18

complex of several proteins respond to the neurotransmitter acetylcholine

Question 19

what initiates metabolic changes

Answer 19

when transmitter binds with receptor ion channels are opened allowing ions to traverse the membrane & initiate metabolic changes

Question 20

efficiency of receptors depend on

Answer 20

receptors sensitivity to neurotransmitters once they are released in the synapse

Question 21

receptors sensitivity to neurotransmitters depends on

Answer 21

• number of receptors available
• affinity for the neurotransmitter
• efficiency of the receptor (high or low)

Question 22

based on sensitivity there are three type of receptors 3

Answer 22

• ion linked receptors (ionotropic) protein structures once binds with neurotransmitter open ion channels within milliseconds
• g proteins receptors whose actions are linked with binding of guanine ( guanyl) nucleotides
• membrane linked kinase receptors

Question 23

neuron cells containing dopamine are located in

Answer 23

nigrostiatal pathways
mesolimbic pathways
mesocortical pathways
tuberoinfundibular pathways

Question 24

members of the D1 like family

Answer 24

• D1 & D5

- activation is excitatory

Question 25

members of the D2 like family

Answer 25

- D2 D3 & D5 - activation is inhibitory - most relvant in psychiatry

Question 26

clinical potency of antipsychotic drugs is related to

Answer 26

their binding affinity to D2 recptors in the caudate & putamen whose blockade results in unwanted motor disturbances eg extra pyramidal side effects (pseudoparkinsonism )

Question 27

acts as prolactin release inhibiting factor in the anterior pituitary

Answer 27

Dopamine

Question 28

dopamine precursor used to treat parkinsonism & its associated depression

Answer 28

Ldopa (levodopa)

Question 29

synthesis of dopamine

Answer 29

tyrosine ⇣ tyrosine hydroxylase (tetrahydrobiopterin) dopa ⇣ L-aromatic amino acid decarboxylase (pyridoxal phosphate) dopamine

Question 30

synthesis of adrenaline and epinephrine

Answer 30

dopamine ⇣ Dopamine-beta hydroxylase (ascorbic acid) noradrenaline and adrenaline ⇣ Phenylethanolamine N-methyltransferase adrenaline and epinephrine

Question 31

breakdown of dopamine

Answer 31

``` Dopamine ⇣ catechol-o-methyltransferase (COMT) 3-Methoxy-4hydroxy-Phenylenthylamine ⇣ monoamine oxidase (MAO) 3-Methoxy-4hydroxy-Phnylacteal Dehyde ⇣ aldehyde dehydrogenase (ALDH) Homovanilic (HVA) (3-Methoxy-4hydroxy-phenylacetic) 🚅 ⇣ transported for excretion (COMT) Dihydroxyphenylactic acid ⇣ aldehyde dehydrogenase (ALDH) Dihydrophenyl-Acetaldehyde ⇣ monoamine oxidase (MAO) Dopamine ```

Question 32

where are noradrenergic neurons located

Answer 32

locus ceruleus within the pons

Question 33

improve depression

Answer 33

tricyclic antidepressants and monoamino oxidase inhibitors (MAOIs)

Question 34

side effects of antidepressants and MAOIS

Answer 34

sedation and hypotension

Question 35

useful in the management of heroin withdrawal symptoms

Answer 35

clonidine an alpha 2 agonist antihypertensive | stimulate pre synaptic alpha 2 receptors minimising the adrenergic activity associated with withdrawal symptoms

Question 36

treatment of lithium-induced tremors, social phobia and akathisia

Answer 36

propranolol (inderal) beta blocker

Question 37

highest concentration of serotonin neurons is in the

Answer 37

upper pons and mid-brain

Question 38

acetylcholine neurons are located in the

Answer 38

mid- and hind-brain and have projections from the nucleus basalis of Meynet to the hippocampus.

Question 39

excessive blockade of the central nervous cholinergic receptors leads to

Answer 39

confusion and delirium condition referred as narcoleptic malignant syndrome

Question 40

H1 receptor

Answer 40

blockade is the mechanism of action of anti allergic medications

Question 41

H2 receptor

Answer 41

doxepin (antidepressant)

Question 42

gamma amino butyric acid (GABA) and glutamate have high concentrations the

Answer 42

amygdala basal ganglia hypothalamus the limbic system but available all over the cns

Question 43

benzodiazepines alcohol & barbiturate act on

Answer 43

GABA receptor complex

Question 44

main inhibitory neurotransmitter in the cns

Answer 44

GABA

Question 45

main excitatory in the cns

Answer 45

glutamate

Question 46

peptides regulate

Answer 46

stress and pain

Question 47

bruxism

Answer 47

grinding of teeth given clonazepam or clonidine