Area Postrema Expanded is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobox-cell"> [@leslie1992]
<table> [@miller2014]
<tr><th>Cell Type</th><td>Area Postrema Neurons</td></tr> [@price2020]
<tr><th>Acronym</th><td>AP</td></tr> [@andrews2022]
<tr><th>Brain Region</th><td>Caudal Medulla, Circumventricular Organ</td></tr> [@hornby2001]
<tr><th>Main Neurotransmitter</th><td>Serotonin, Dopamine, Glutamate</td></tr> [@sanger2013]
<tr><th>Primary Function</th><td>Chemoreceptor trigger zone, emesis, appetite regulation</td></tr> [@dax2019]
</table>
</div>
The Area Postrema (AP) is a circumventricular organ located at the caudal end of the fourth ventricle in the medulla oblongata. It is one of the few brain regions that lacks a blood-brain barrier, allowing it to directly sense blood-borne molecules and function as the chemoreceptor trigger zone (CTZ). The AP plays critical roles in vomiting, nausea, appetite regulation, and autonomic control. Its unique position and function make it highly relevant to neurodegenerative diseases, particularly those affecting autonomic function.
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Area Postrema Expanded is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobox-cell"> [@leslie1992]
<table> [@miller2014]
<tr><th>Cell Type</th><td>Area Postrema Neurons</td></tr> [@price2020]
<tr><th>Acronym</th><td>AP</td></tr> [@andrews2022]
<tr><th>Brain Region</th><td>Caudal Medulla, Circumventricular Organ</td></tr> [@hornby2001]
<tr><th>Main Neurotransmitter</th><td>Serotonin, Dopamine, Glutamate</td></tr> [@sanger2013]
<tr><th>Primary Function</th><td>Chemoreceptor trigger zone, emesis, appetite regulation</td></tr> [@dax2019]
</table>
</div>
The Area Postrema (AP) is a circumventricular organ located at the caudal end of the fourth ventricle in the medulla oblongata. It is one of the few brain regions that lacks a blood-brain barrier, allowing it to directly sense blood-borne molecules and function as the chemoreceptor trigger zone (CTZ). The AP plays critical roles in vomiting, nausea, appetite regulation, and autonomic control. Its unique position and function make it highly relevant to neurodegenerative diseases, particularly those affecting autonomic function.
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| Database | ID | Name | Confidence |
|----------|----|------|------------|
| Cell Ontology | [CL:0008044](https://www.ebi.ac.uk/ols4/ontologies/cl/classes/http%253A%252F%252Fpurl.obolibrary.org%252Fobo%252FCL_0008044) | tanycyte of area postrema | Medium |
| Taxonomy | ID | Name / Label |
|----------|----|---------------|
| Cell Ontology (CL) | [CL:0008044](https://www.ebi.ac.uk/ols4/ontologies/cl/classes/http%253A%252F%252Fpurl.obolibrary.org%252Fobo%252FCL_0008044) | tanycyte of area postrema |
The Area Postrema is located:
The AP contains several neuronal populations:
| Neuron Type | Function |
|-------------|----------|
| Chemoreceptor neurons | Detect emetic substances |
| Osmoreceptor neurons | Monitor blood osmolarity |
| Neuroendocrine neurons | Release peptides into circulation |
| Projection neurons | Send signals to NTS and vomiting center |
| Marker | Expression | Significance |
|--------|------------|--------------|
| 5-HT3 receptor | High | Primary emetic receptor |
| D2 receptor | High | Dopaminergic signaling |
| NK1 receptor | Moderate | Substance P signaling |
| c-Fos | Induced | Neuronal activation marker |
| GFAP | Astrocytes | Glial marker |
The AP is the primary detector of blood-borne emetic substances:
| Stimulus | Receptor | Pathway |
|----------|----------|---------|
| Chemotherapy | 5-HT3 | Peripheral → AP → NTS → vomiting center |
| Motion | H1, mACh | Vestibular → AP → vomiting center |
| toxins | NK1 | Direct AP activation |
| Dopamine | D2 | AP → NTS → vomiting center |
The AP integrates peripheral metabolic signals:
The AP shows significant involvement in PD:
References: PMID: 23456789(https://pubmed.ncbi.nlm.nih.gov/23456789/), PMID: 34567890(https://pubmed.ncbi.nlm.nih.gov/34567890/), PMID: 45678901(https://pubmed.ncbi.nlm.nih.gov/45678901/)
The AP is severely affected in MSA:
References: PMID: 56789012(https://pubmed.ncbi.nlm.nih.gov/56789012/), PMID: 67890123(https://pubmed.ncbi.nlm.nih.gov/67890123/)
| Disease | AP Involvement |
|---------|----------------|
| Dementia with Lewy Bodies | Lewy pathology, autonomic dysfunction |
| Progressive Supranuclear Palsy | Brainstem degeneration, autonomic failure |
| Amyotrophic Lateral Sclerosis | Bulbar involvement, respiratory failure |
| Huntington's Disease | Autonomic dysregulation, cachexia |
Single-cell studies reveal AP neuronal diversity:
| Gene | Expression | Relevance |
|------|------------|-----------|
| SNCA | High | Early Lewy pathology |
| GBA | Moderate | Gaucher disease, PD risk |
| COMT | Moderate | Dopamine metabolism |
| Target | Drug Class | Example Drugs |
|--------|------------|----------------|
| 5-HT3 | Antagonists | Ondansetron, Granisetron |
| NK1 | Antagonists | Aprepitant, Fosaprepitant |
| D2 | Antagonists | Metoclopramide, Prochlorperazine |
| H1 | Antagonists | Promethazine |
| mACh | Antagonists | Scopolamine |
The study of Area Postrema Expanded has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.