Imbalances in neurotransmitters leading to diseases

Question 1

What is Parkinson’s disease

Answer 1

-Parkinson’s disease is a brain disorder that affects the coordination of movement by causing a loss of neurones in some areas of the brain

Question 2

Symptoms of Parkinson’s disease

Answer 2

-Tremor to specific parts of the body
-Slow movements
-Muscles become stiff and inflexible
-Changes to speech
-Difficulty with balance

Question 3

Causes of Parkinson’s

Answer 3

Individuals with Parkinson’s disease produce an insufficient amount of dopamine due to the loss of dopamine producing neurones in the brain
-This means that less dopamine is released into the synaptic cleft and less dopamine binds to receptors on the postsynaptic membrane
-Therefore less sodium ion channels open, less sodium ions move into the axon, and the threshold potential is much less likely to be reached
-This results in fewer action potentials being generated, causing symptoms such as tremors and slow movement

Question 4

Drug treatments for Parkinsons

Answer 4

-Dopamine agonists are drugs that produce the same effect as dopamine by binding to receptors on the post synaptic neurone
-Dopamine Precursors are chemicals that can be converted to dopamine in the neurone (i.e L-Dopa)
-Enzyme Inhibitors -MAOB inhibitors inhibit the action of the enzyme MAOB which usually breaks dopamine in the synaptic cleft, raising levels of dopamine in the brain

Question 5

Possible Parkinsons treatments

Answer 5

Gene therapy: Addition of genes to the affected cells to either increase dopamine production or prevent the destruction of dopamine producing cells
Stem therapy: Using stem cells to replace the lost dopamine producing cells in the brain

Question 6

Depressions association with neurotransmitters

Answer 6

-Dopamine is linked to low levels of the neurotransmitter serotonin
-Serotonin transmits nerve impulses in areas of the brain that control mood
-Additionally other brain chemicals such as noradrenaline and dopamine are also associated with depression

Question 7

Treatments of Depression

Answer 7

-Antidepressants (general term) are drugs that increase levels of relevant neurotransmitters in the brain i.e dopamine and serotonin
-SSRIs are a class of antidepressant that prevents the reuptake of serotonin at the synapse, this increases overall levels of serotonin in the brain
-MAOAB inhibitors inhibit the enzyme MAOAB that normally breaks down neurotransmitters in the synapse, increasing levels of neurotransmitters in the brain