CoursePsychopharmacology Introduction

The drug-action atlas

Enter through a molecule, a synapse, or a brain circuit. Change the conditions and trace what happens next.

All learning models

Explore the system

Change the mechanism, watch the synapse

Start with normal transmission. Select a molecular target and compare its acute and chronic consequences.

Change the mechanism, watch the synapse

Diagram zoom

Original schematic. Positions show relationships; structures and concentrations are not to scale.

This combined teaching diagram compares monoamine clearance, an ionotropic response and glutamate–glia recycling. Most dopamine, norepinephrine and serotonin receptors signal through G proteins, rather than directly opening a channel.

Signal → release → binding → clearance

Transporters clear monoamines; separate vesicular transporters load vesicles. Receptors and enzymes occupy different compartments.

Illustrative receptor activity: 25% · Basal activity: 25%

Model units; no clinical dose or treatment prediction.

Drug mechanismRepeated exposureAfter stopping

Functional receptor availability: 5

Inspect a structure

Presynaptic axon terminal

Contains vesicles, synthesis machinery, and intracellular enzymes.

Animate the diagram

On a small screen, pan the diagram or increase zoom. Named controls provide the same exploration by keyboard.

Sources and model limits

Original schematic. Positions show relationships; structures and concentrations are not to scale.

Julien's Primer of Drug Action · 15 · 3 · Change the mechanism, watch the synapse · PDF 34, 35, 36, 37, 38 · 3.3, 3.7, 3.10
Professor deck 3 · Monoamine clearance / transporters · PDF 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
IUPHAR recommendations · Supplement: inverse agonism and allosteric terminology
Assay Guidance Manual · Supplement: agonists, antagonists and inverse agonists
Monoamine transporter research · Supplement: amphetamine-related vesicular and membrane transport

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The drug-action atlas

Enter through a molecule, a synapse, or a brain circuit. Change the conditions and trace what happens next.

All learning models

Explore the system

Change the mechanism, watch the synapse

Start with normal transmission. Select a molecular target and compare its acute and chronic consequences.

Change the mechanism, watch the synapse

Diagram zoom

Original schematic. Positions show relationships; structures and concentrations are not to scale.

Signal → release → binding → clearance

Transporters clear monoamines; separate vesicular transporters load vesicles. Receptors and enzymes occupy different compartments.

Illustrative receptor activity: 25% · Basal activity: 25%

Model units; no clinical dose or treatment prediction.

Drug mechanismRepeated exposureAfter stopping

Functional receptor availability: 5

Inspect a structure

Presynaptic axon terminal

Contains vesicles, synthesis machinery, and intracellular enzymes.

Animate the diagram

On a small screen, pan the diagram or increase zoom. Named controls provide the same exploration by keyboard.

Sources and model limits

Original schematic. Positions show relationships; structures and concentrations are not to scale.

Julien's Primer of Drug Action · 15 · 3 · Change the mechanism, watch the synapse · PDF 34, 35, 36, 37, 38 · 3.3, 3.7, 3.10
Professor deck 3 · Monoamine clearance / transporters · PDF 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
IUPHAR recommendations · Supplement: inverse agonism and allosteric terminology
Assay Guidance Manual · Supplement: agonists, antagonists and inverse agonists
Monoamine transporter research · Supplement: amphetamine-related vesicular and membrane transport