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Nervous system > Neurotransmitters > Flashcards

Flashcards in Neurotransmitters Deck (21)
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1
Q

What are neurotransmitters?

A
  • Chemicals that transmit signals from a neuron to an adjacent cell (nerve, muscle, organ, gland)
  • Can stimulate or inhibit target cell
  • Synaptic transmission is virtually always unidirectional
  • Activate receptor to react
  • Many work at multiple sites - action detected by receptor rather than neurotransmitter
2
Q

Which neurotransmitter normally acts on blood vessels?

A

Noradrenaline

3
Q

Which enzyme regulates presynaptic store of catecholamines?

A

Monoamine oxidase

4
Q

What do monoaminoxidases do?

A

Break down caracholamines in pre-synapse

5
Q

Into which class does the Beta 1 receptor fall?

A

G-protein linked

6
Q

What is the main role of the alpha 2 receptors in the PNS?

A

Terminating presynaptic NA release

7
Q

What does serotonin do?

A
  • 13 receptor sub-types in multiple sites, regulating processes and other neurotransmitters and hormones
  • Some broken down by monoamine oxidase but a lot taken back up and re-used
  • Antidepressants SSRIs - selective serotonin re-uptake inhibitors
  • Medications block receptor
  • Longer stays in synapse, better chance of signal getting through = increased mood
8
Q

Effects of 5-HT

A
  • CNS: mood, memory, aggression, appetite, sleep, addiction
  • Gut: motility, emesis (5-HT3)
  • CVS: vasoconstriction, HR
  • Blood: platelet activation
9
Q

When ACh binds at the NMJ postsynaptic receptor, what ion influx generates AP at end plate?

A

Na+

10
Q

Main peripheral neurotransmitters and receptors

A
  • Nicotinic receptors: neuromuscular junction (N2) and autonomic ganglia (N1)
  • Muscarinic receptors: parasympathetic post-ganglionic (M1, M2…), sympathetic = sweating
11
Q

What are the two types of noradrenaline?

A
  • Sympathetic post-ganglionic (alpha1, beta1)

- Presynaptic inhibitory (alpha2)

12
Q

Function of ACh

A

Motor function regulation (basal ganglia vs dopamine), emotion, arousal

13
Q

Function of dopamine

A

Motor function regulation (basal ganglia vs ACh), memory, emesis, regulation of hormone release (GH, prolactin)

14
Q

Function of noradrenaline

A

Memory, arousal, circadian rhythm, endorphin release in spinal cord (inhibits nociception)

15
Q

Function of serotonin

A

Mood, memory, appetite, sleep, endorphin release in spinal cord (inhibits nociception)

16
Q

Function of GABA

A

Main inhibitory neurotransmitter, GABAa (Cl- channel linked) and GABAb (GPCR)

17
Q

Function of glutamate

A

Excitatory neurotransmitter, NMDA, KA, AMPA sub-types

18
Q

Functions of endorphins/enkephalins

A

Inhibits nociception in dorsal horn of spinal cord

19
Q

Function of substance P

A

Amplifies nociception in dorsal horn of spinal cord

20
Q

What is the triad of Parkinson’s disease?

A

Tremor, rigidity, bradykinesia

21
Q

Treatment for Parkinson’s

A

Treatment revolves around boosting dopamine action either by giving more dopamine substrate (L-DOPA) or blocking dopamine breakdown (with COMT or MAO inhibitors) or by using dopamine receptor agonists