Principles of Drug Action on Neurotransmission

Flashcards about principles of drug action on neurotransmission.

What neurotransmitter is typically found at sympathetic terminals?

Noradrenaline (NA)

Which neurotransmitter is associated with parasympathetic terminals, ganglia, and the neuromuscular junction (NMJ)?

Acetylcholine (ACh)

Name a neurotransmitter primarily found in parts of the CNS.

Dopamine (DA) or Serotonin (5-HT)

What is the location of ganglia in the sympathetic nervous system?

Typically close to the spinal cord in the paravertebral chain.

What is the location of ganglia in the parasympathetic nervous system?

Close to or inside target tissues

What type of channel is involved in the neuroeffector junction's depolarization process?

Voltage operated calcium channel

What is the effect of hemicholinium on ACh synthesis?

Inhibits precursor uptake

What is the effect of AMPT on NA synthesis?

Inhibits the enzyme cascade

What is the effect of reserpine on neurotransmitter storage?

Inhibits storage (NA)

What is L-DOPA used for therapeutically?

To increase dopamine levels in the brains of patients with Parkinson’s disease

What process does guanethidine inhibit, though it's only of minor importance to its overall effect?

Terminal depolarization (NA)

What does conotoxin inhibit?

Calcium entry (Ca)

What process does Botulinum toxin inhibit?

Vesicle fusion (ACh)

What effect do amphetamine and guanethidine have on noradrenaline (NA)?

Displace NT (NA)

What effect does clonidine have on noradrenaline release?

Inhibits NA release via presynaptic α2 receptor agonism

What process is affected by cocaine?

Reuptake (NA)

What process is affected by fluoxetine?

Reuptake (5-HT)

What is the mechanism of action of neostigmine?

Inhibits enzyme (ACh)

What two factors define an agonist?

Affinity and efficacy

What defines an antagonist in terms of receptor action?

Affinity but no efficacy; it blocks the binding site & inhibits agonist action