Norepinephrine/Epinephrine

Question 1

Norepinephrine

Answer 1

• Synthesis is pons in metencephalon (locus ceruleus)
• Synthesized from tyrosine
• Released by non directed synapses
o Excitatory functions, maximizes oxygen and glucose supply to other organs, also important for attention, learning and memory
• Also synthesized and released by post-ganglionic neurons in SNS
• Acts as both neurotransmitter and hormone
• Acts mostly in CNS

Question 2

Epinephrine

Answer 2

• Made from Tyrosine
• Synthesis mainly in periphery (medulla of adrenal glands on kidney)
• Same receptors as norepinephrine
• Both hormone and neurotransmitter (Periphery- hormone, CNS- neurotransmitter-limited role)

Question 3

Adrenergic Receptors

Answer 3

• Alpha 1, 2, beta 1, 2 are metabotropic
• Bind to epinephrine and norepinephrine
• Responses to arousing, activating, stressful event (prepare for flight or flight)

Question 4

ADHD

Answer 4

• Affects alpha 2 receptors

* Atomoxetine as treatment (prevent reuptake of NE to improve attention by blocking reuptake transmitter)

Question 5

Monoamine Oxidase Inhibitors:

Answer 5

• Enzyme that break down monoamines
• Found in terminals of neurons that release monoamines
• Formerly used to treat depression
• Not specific, caused lots of side effects

Question 6

Beta Blockers

Answer 6

• Used to treat anxiety
• Can’t cross blood brain barrier
• Reduces effects in periphery (i.e. heart rate, sweat), but doesn’t do anything in the brain
• i.e. propranolol

Question 7

Cocaine

Answer 7

• Increases activity of Dopamine and norepinephrine
• Blocks reuptake
• Analgesic properties (reduced pain perception)
• Increased dopamine can lead to addiction

Question 8

Cocaine Psychosis

Answer 8

• Anxiety, increased pulse and blood pressure, dilation of pupils, faster breathing, insomnia…etc
• Bizarre, erratic, violent behaviour and paranoid psychosis if discontinued
• Sometimes misdiagnosed as paranoid schizophrenia