targetsTarget

5-HT3 receptor (HTR3A)

The serotonin receptor on the gut's vagus nerve endings and in the brainstem vomiting centre that chemotherapy triggers. Ondansetron and palonosetron block it, the foundation of modern anti-sickness treatment.

Chemotherapy damages enterochromaffin cells in the gut lining, releasing serotonin that activates 5-HT3 receptors on vagal afferents and in the area postrema to provoke acute vomiting. 5-HT3 antagonists, first ondansetron in 1991 and later granisetron and the long-acting palonosetron, block this pathway and transformed the experience of cisplatin-based and anthracycline-based chemotherapy. They are combined with an NK1 antagonist and dexamethasone for highly emetogenic regimens; constipation, headache and QT prolongation are the main side effects.

5-HT3 receptor (HTR3A): what it is and how drugs act on it · animated generic schematic, not to scale

Target · the protein and the cell it sits on
Drug · antibody, small molecule, cell or radioligand
Effect · signal, damage or kill

In plain words · The serotonin receptor on the gut's vagus nerve endings and in the brainstem vomiting centre that chemotherapy triggers. Ondansetron and palonosetron block it, the foundation of modern anti-sickness treatment.

1 · What it is
The serotonin receptor on the gut's vagus nerve endings and in the brainstem vomiting centre that chemotherapy triggers. Ondansetron and palonosetron block it, the foundation of modern anti-sickness treatment.
2 · What goes wrong in cancer
Ligand-gated ion channel for serotonin on vagal afferents and in the brainstem chemoreceptor trigger zone; blocked by setron antiemetics.
3 · How drugs use it
No product in this corpus aims at 5-HT3 receptor (HTR3A) yet. Drugs bind the molecule precisely: to switch it off, flag the cell for the immune system, or deliver a payload.