Flashcards in Autonomic pharmacology pt. 3: Autacoids Deck (32)
Leukotrienes are generated from _______ using the enzyme ________.
arachidonic acid, lipooxygenase
In which major organ do leukotrienes bind receptors primarily? What does this cause?
Lungs. Causes bronchoconstriction
How is asthma commonly treated?
With leukotriene receptor antagonists.
In which organ(s) is/are COX-1 found?
GI tract and kidneys
In which organ(s) is/are COX-2 found?
What is one AE that inhibition of prostacyclin (PGI2) can cause?
MI or thrombotic stroke
Why do NSAIDs cause AEs like GI ulceration and bleeding?
They non-selectively inhibit cyclooxygenases 1 and 2. COX-1 produces PGE2 which makes the protective mucosal barrier in the GI tract. COX-1 also produces thromboxane TXA2 which promotes platelet aggregation.
What do prostacyclins like PGI2 do? Which enzyme makes it? Does aspirin affect COX-2?
Inhibit platelet aggregation and vasodilate. COX-2 makes it. Aspirin does not affect COX-2 in small doses, and that is the basis for its blood-thinning effects. It inhibits COX-1, preventing TXA2 formation.
Do prostaglandins produced in the kidney help promote healthy renal blood flow?
What are the two types of histamine receptors? Which one is involved in allergic reactions and therefore is a target of anti-histamines?
H-1 and H-2. H-1 is involved in allergic reactions and is a target of diphenhydramine and loratidine.
Can diphenhydramine cross the blood-brain barrier? What is the clinical significance of this?
It can because it is lipophilic. It is therefore a sedative because it can bind H-1 receptors in the CNS.
Where are H-2 receptors primarily found? What does stimulation of these receptors do? What drugs target these receptors?
Found in the stomach. Stimulation results in parietal cell acid secretion. Drugs target these receptors to treat acid reflux: ranitidine, nizatidine, famotidine.
What do bradykinins do?
Vasodilation and pain
What is the relationship between ACE and bradykinins? What do ACE inhibitors do?
ACE degrades bradykinins. ACE inhibitors increase endogenous bradykinins and also reduce angiotensin II, resulting in vasodilation.
Does increased serotonin levels in the brain improve mood and sleep?
In which organ is the majority of serotonin found?
What does serotonin do to smooth muscle?
Constriction (remember serotonin agonist treat migraines in phase 2 - vasodilation)
What two molecules are responsible for symptoms of allergy? What is the Triple response of Lewis?
Histamine and kinins causes Triple response of Lewis: heat, itching, swelling, pain (HISP).
Where are mast cells located?
Perivascularly and close to nerve endings
Can mast cells release cytokines without degranulating?
Does mast cell degranulation affect all body organs?
What does nitric oxide do?
Which two cell types have lots of histamine?
Basophils, mast cells
What is measured in a 24-hour urine collection to diagnose systemic mastocytosis?
N-methylhistamine/1,4-methylimidazole acetic acid
Why are opioids often given in conjunction with antihistamines?
Opiates degranulate mast cells causing histamine release and hypotension, so antihistamines are given.
What is Cemetidine?
A H-2 receptor antagonist that treats acid reflux and also inhibits microsomal liver CYP450 resulting in increased estrogen levels --> gynecomastia and psychological problems
What's up with H. pylori?
It causes gastritis and likes low pH in GI tract.
What do gastrin and acetylcholine do to the stomach?
Increase gastric acid secretion
Selective serotonin reuptake inhibitors (SSRIs) can be used to treat _______. They also antagonize ________ receptors.
depression. They antagonize Ach muscarinic receptors