Dopamine

Question 1

Dopamine

Answer 1

• Chemical (catecholamine) made in our brain
• Both vertebrates and invertebrates make
  dopamine
• Dopamine’s role is dictated by the repertoire of
  dopamine receptors in an organism.
• The biosynthetic pathway is highly conserved.
• Dopamine can also be converted to nor-adrenalin and adrenalin.
• Dopamine acts as a neurotransmitter communicating between
  neurons/nerve cells in our brain

Question 2

What stimulates dopamine release?

Answer 2

• Many of our actions during the day release dopamine.
• The brain has a basal level of dopamine circulating which
  helps us determine what is a ‘good’ or rewarding
  experience.

Question 3

Dopamine Release Cycle - Neuroadaptation

Answer 3

• Dopamine high will trigger the body
  to decrease dopamine levels.
• However, our body “overshoots”
  leading to a crash in dopamine levels.
• Dopamine deficit is when our
  dopamine levels are below baseline.
• Length of time of dopamine deficit is
  dictated by numerous factors,
  including the concentration of
  dopamine at the peak of release.

Question 4

Biochemistry - Dopamine Deficit

Answer 4

• Dopamine released from
  presynaptic or “sending”
  neuron.
• Dopamine binds to receptor on
  post-synaptic, or “receiving”
  neuron
• This leads to a signalling
  cascade that promotes reward
  attainment.

When our body wants to decrease dopamine levels it:
(a) Internalizes dopamine receptors in the post-synaptic nerve cell.
(b) Activates a secreted dopamine degrading enzyme that deactivates
circulating dopamine
(c) Expresses a re-uptake dopamine transporter in the presynaptic cell
to facilitate its re-uptake back into this cell.

Question 5

Dopamine

Answer 5

• Natural dopamine highs release small amounts of dopamine
• Synthetic (human-made) compounds trigger much larger dopamine hits
  Baseline + Alcohol
• The higher the dopamine peak, the longer the crash, dopamine deficient
  state.
• Synthetic stimuli have larger crashes, prolonging dopamine deficient state
• This cycle will induce addiction

Question 6

Alcoholism and Dopamine

Answer 6

• Second exposure to alcohol
  during dopamine deficit means
  that the peak will not reach
  same height
• Addiction happens when this cycle can’t be broken
• Therefore more alcohol is
  needed to experience the
  same pleasure

Question 7

Susceptibility to Addiction

Answer 7

Some individuals are more or less susceptible to addiction, just like some
people are more/less susceptible to cancer
* Addiction is a disease… not a choice or an inability to resist temptation.
* Addiction can lead to
death*
* Matthew Perry’s interview on
CANVAS
* Addiction to “cheap
dopamine” hits can also lead
to poor mental health
* anxiety, stress, feeling
overwhelmed, insomnia,
irritability.