Toggle navigation
PathBank
Browse
Pathways
Table of Primary Pathways
Compounds
Proteins
Search
Advanced Text Search
ChemQuery Structure Search
Molecular Weight Search
Sequence Search
Analyze
Over-Representation Analysis
Path-MAP Analysis
Pathway Enrichment Analysis
About
About PathBank
Statistics
Style Guide
Other Databases
Pathway Legend
Pathway Category Definitions
PathWhiz
Downloads
Contact Us
Quantitative metabolomics services for biomarker discovery and validation.
Specializing in ready to use metabolomics kits.
Your source for quantitative metabolomics technologies and bioinformatics.
Loading Pathway...
Error: Pathway image not found.
5-
hydroxytryptamine
receptor 3A
Voltage-
dependent
P/Q-type
calcium channel
subunit
alpha-1A
Voltage-
dependent
L-type calcium
channel subunit
beta-1
Voltage-
dependent
calcium channel
subunit
alpha-2/delta-2
Synaptic
vesicular amine
transporter
Sodium-
dependent
serotonin
transporter
Tryptophan
5-hydroxylase 1
Aromatic-L-
amino-acid
decarboxylase
Ca
+
Serotonin
Serotonin
Ondansetron
Ca
+
Serotonin
Ondansetron
Ondansetron
L-Tryptophan
Tetrahydrobiopterin
O
2
5-Hydroxy-L-tryptophan
4a-Hydroxytetrahydrobiopterin
CO
2
Na
+
Na
+
Fe2+
Pyridoxal
5'-phosphate
Vagus nerve
stimulation
Activation of
emetic reflex
Activation of
emetic reflex
Synaptic Vesicle
Cytosol
Cytosol
Presynaptic Neuron
Postsynaptic Neuron
Synapse
Ondansetron competitively
blocks 5HT3A receptors
leading to antiemetic
effects
Serotonin is synthesized at
the raphei nuclei and stored
in synaptic vesicles at the
nerve terminal
Serotonin (5HT3A) receptors,
acting centrally in the
chemoreceptor trigger zone
(area postrema) is
stimulated to cause nausea
and vomiting
Brain
Raphei nuclei produces
serotonergic neurons
Blood vessel
passive diffusion
Ondansetron is administered
orally
Ondasetron selectively
blocks 5HT3A receptors in
the chemoreceptor trigger
zone centrally
Chemoreceptor Trigger Zone
5HT3 receptors are also
located on the vagus nerve
terminals in the periphery
vagus nerve senses nausea
and vomiting triggers within
the gastrointestinal tract
(GIT), such as stomach
irritants.
smooth muscle of the GIT
5HT3A receptors present on
vagal afferent nerve
terminals are activated by
serotonin released from
enterochromaffin cells in
the gut or by circulating
emetogenic substances.
HTR3A
CACNA1A
CACNB1
CACNA2D2
SLC18A2
SLC6A4
TPH1
DDC
Calcium
Serotonin
Serotonin
Ondansetron
Calcium
Serotonin
Ondansetron
Ondansetron
L-Tryptophan
Tetrahydrobiopterin
Oxygen
5-Hydroxy-L-
tryptophan
4a-
Hydroxytetrahydrobiopterin
Carbon dioxide
Sodium
Sodium
Vagus nerve
stimulation
Activation of
emetic reflex
Activation of
emetic reflex