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| | + | ==The Vomit Reflex== |
| | + | |
| | + | *Emesis is the process of vomiting |
| | + | |
| | + | *Retching involves the abdominal and chest walls contracting |
| | + | |
| | + | *Vomiting includes retching and the action of the diaphragm |
| | + | |
| | + | *Diaphragm moves caudal to open the cardia |
| | + | |
| | + | *Gastrointestinal tract have protective stimuli to recognise harmful products ingested. The mechanoreceptors and chemoreceptors respond using viscerent afferent pathways. |
| | + | |
| | + | *Medulla co-ordinates process |
| | + | |
| | + | *Chemoreceptive trigger zone in the 4th ventricle responds to blood and CSF |
| | + | |
| | + | *Inputs also from inner ear and higher centres |
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| | + | *Emetic agents |
| | + | **Histamine |
| | + | **ACh |
| | + | **Dopamine |
| | + | **Catecholamines |
| | + | **5-hydroxytryptamine |
| | + | |
| | + | *Anti-emetic agents |
| | + | (INCLUDE HERE) |
| | + | |
| | + | ==Species Differences== |
| | + | |
| | + | ===Equine=== |
| | + | *The horse cannot vomit |
| | + | |
| | + | ==Links== |