4 main regions that control vomiting

Question 1

the cerebrum - higher centers

Answer 1

• mainly controlled by acetylcholine (also dopamine, histamine, opioid and alpha 2 receptors)
• stimulated when activated by neurotransmitters
• can be overly stimulated by unpleasant smells/sights or neurological/phycological causes

Question 2

the chemoreceptor trigger zone (CTZ)

Answer 2

• controlled by dopamine but can be activated by neurotransmitters such as serotonin, histamine, acetylcholine & narcotics (drugs)
• liver disease & endotoxin toxicity can activate the CTZ too

Question 3

the vomiting center

Answer 3

• activated by acetylcholine
• the final step in vomit stimulation & signal transmission begins
• receptors also include NK1 & muscarinic receptors
• activation of these center results in vomiting as it receives signals from the higher centers & CTZ

Question 4

regions in the GIT involved

Answer 4

• small intestines
• stomach

both are stimulated by gastrointestinal upset and sympathetic/parasympathetic receptors such as acetylcholine, serotonin, histamine, opiods, etc

Question 5

the most IMPORTANT receptors

Answer 5

• acetylcholine (Higher centers & vomiting center & GIT)
• dopamine (higher centers, CTZ)
• histamine (higher centers, CTZ, GIT)
• neurokinin (vomiting center)
• serotonin (CTZ, GIT)
• opioids (higher center, GIT)
• alpha 2 receptors