Synaptic Transmission: Targets of Drug Action

Question 1

Steps of Neurotransmission

Answer 1

1) Neurotransmitter Synthesis
2) Vesicular Storage
3) Synaptic Release
4) Receptor Binding
5) Termination of Action

Question 2

Manipulate Synthesis

Answer 2

L-DOPA
Carbidopa
Metyrosine
ACE Inhibitor

Question 3

Manipulate Storage

Answer 3

Reserpine

Tyramine

Question 4

Manipulate Release

Answer 4

Bretylium
Botulinum
Tetanus
Amphetamine (indirect)

Question 5

Manipulate Receptor Binding

Answer 5

Naloxone/Naltrexone

Phenylephrine

Question 6

Manipulate Termination Action

Answer 6

• Monoamine Oxidase (MAO) Inhibitors
• COMT
• Cocaine
• Tri-cyclic antidepressants
• NE- selective reuptake inhibitors
• SSRI

Question 7

Metyrosine

Answer 7

• Hypertension

- Competitive Inhibition of Tyrosine Hydroxylase

Question 8

Reserpine

Answer 8

• Hypertension
• Inhibits Vesicular Monoamine Transporter (VMAT) uptake of monoamines
• Can cause depression with BBB crossing- give in low doses

Question 9

Bretylium

Answer 9

• Ventricular Arrythmia

- Inhibit the AP generation and Ca dependent synaptic vesicle fusion

Question 10

Cocaine

Answer 10

• Surgical- analgesia

- Blocks monoamine re-uptake

Question 11

Amphetamine or Ephedrine

Answer 11

• Narcolepsy, ADHD

- Reverse monoamine reuptake transporters

Question 12

Naloxone, Naltrexone

Answer 12

• Opioid overdose or dependence

- Non-peptide blockers of opioid receptors in CNS

Question 13

SSRI

Answer 13

• Depression/Anxiety

- Selective inhibition of seretonin reuptake transporter

Question 14

ACE Inhibitor (lisinopril)

Answer 14

• Hypertension

- Inhibits cleavage of ang 1 to ang 2

Question 15

Phenylephrine

Answer 15

• Hypotension during surgery

- Direct agonist of adrenergic receptor

Question 16

MAO Inhibitors

Answer 16

• Depression

- Blockade of cytoplasmic metabolism of monoamines

Question 17

L-DOPA

Answer 17

• PArkinson’s

- Dopamine precursor loading, non selective and can cause heart issues

Question 18

Carbidopa

Answer 18

• PArkinson’s
• Blocks L-DOPA conversion to dopamine in the PNS so no adverse side effects, does not cross BBB so efficacy is still there

Question 19

Tyramine

Answer 19

• Dietary, not therapeutic

- Competes with NE for transport into synaptic vesicle

Question 20

Tyrosine Hydroxylase

Answer 20

Rate limiting enzyme for the conversion of tyrosine to DOPA

Question 21

VMAT

Answer 21

“Vesicular Monoamine Transporter” monoamine into the vesicle to protect from cytosolic enzymes

Question 22

Dopamine-B-Hydroxylase

Answer 22

Dopamine to Norepinephrine

Question 23

MAO

Answer 23

Intracellular enzyme that degrades neurotransmitters

Question 24

COMT

Answer 24

Degradative enzyme in the synaptic cleft

Question 25

Acetylsholinesterase

Answer 25

ACh to choline