Pharmacology learning thingy Flashcards
What type of cells produce histamine?
ECL cell
“Enterochromaffin-like cells or ECL cells are a type of neuroendocrine cell found in the gastric glands of the gastric mucosa beneath the epithelium, in particular in the vicinity of parietal cells, that aid in the production of gastric acid via the release of histamine”
What are ECL cells stimulated by?
Gastrin and parasymp (vagus)
How does the vagus innervate ECL/Parietal cells?
Via ACh and Muscarinic (3)
Ant acid salts, what are they,how are they commonly used (+/-), how do they work?
Magnesium/Aluminium - often used together:
-Mg is laxitive
-Al is constipative
Calcium:
-associated with rebound phenomenon
Work by neutralising the acid eg Calcium carbonate +HCl -> CaCl2 +H20 + CO2
Alginaes eg and how do they work?
Eg gaviscon and they work by forming a physical foamy raft like thing that acts as a physical barrier for the acid to head back up to the oesophagus
H2 antagonist work where and eg
Work by blocking th eH2 (stomach histamine) receptor and therefore reducing the amount of acid being pumped into the stomach.
eg Ranitidine
What does the CRTZ recieve triggers from? WHat des it detect?
Chemoreceptor trigger zoe
Samples blood, so triggered by toxins in teh blood.
Innervated by crainial nerves, gut and vestibular system
Where is the vommiting center? What effect can factors (eg…) from the cerebral cortex have on the nausa sensation?
In the medulla
Signals teh gut to initiate vomitting
Pain, emotions, raised intracranial pressure
Toxic nausea/vom is what type?
Severe nausea with recurrent voms that don’t help.
Gut Motility issue nausea/vom is what type?
intermittant nausea then large vom release. Feel full after only small amount of food.
Oropharyngeal irritation nausea/vom has what type of vomming
irritation of the oropharynx can cause nausea and vomiting and if often related to
other pathology such as tumours in this area.
Itracranial nausea/vom has what type of vomming
heaqdache, lowered level of conciousness, vertigo/nausea
inc. motion sickness and nausea from intracranial pressure
Which receptors can be attacked to help prevent CRTZ ?
D2 - dopamine one eg haloperidol, levomepromezine
5HT3 - Ondansetron
What receptors can target Vom venter?
5HT2 - levomepromazine
H1 - levomepromazine, Cyclizine(motion sickness, labyrinthitis
ACh(muscarinic) - Cyclizine/ levomepromazine/
How can receptors in the gut hep?
Increasing motility:
5HT4 - Metoclopramide (also acts on D2)
Macrolides eg Erythromycin (prokinetic)
