Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IC > Histamine/PG > Flashcards

Histamine/PG Flashcards

1
Q

Autocoids

A

endogenous substances in the body (histamine, serotonin, peptides, prostaglandins, leukotrienes)

  • short duration of action, act near site of synthesis/release
  • high levels cause inflammation, pain, bronchospasm, anaphylactic shock
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Histamine

A
  • Synthesized from L-histidine
  • Delivered by degranulation of basophils and mast cells at sites of injury (via IgE cross linking0
  • Acts in brain as NT
  • Enterochromaffin like cells in stomach which activate acid production (H2 receptor)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Immunologic histamine release

A
  • Crosslinked IgE causes degranulation releasing histamine
  • Causing Type 1 allergic reactions- hay fever, urticaria and inflammation and immune modulation (blood vessel dilation, complement activation, cytokine, T and B cell modulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Chemical induced histamine release

A

-morphine, tubocurarine, cpd 48/80, mast cell injury

first two lead to release of histamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cromolyn

A

Inhibits histamine release

Also nedocromil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

H1 receptor mediated response

A

-urticarial response, respiratory neuron singaling, vasodilation via NO release (reflex tachycardia), edema, bronchoconstriction, contraction of intestinal smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

First gen antihistamines

A

Carbinoxamine, dimenhydrinate, diphenhydramine (more sedative effect), hydroxyzine, cyclizine, meclizine, brompheniramine, chlorpheniramine, promethazine, cyproheptadine

anti cholinergic activity causes sedation, anti-motion sickness activity, and some anti emesis (promethazine)

4-6 hrs duration of action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Second gen antihistamine

A

Fexofenadine, loratidine (long acting), cetirizine, azelastine, desloratidine

12-24 hr duration of action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Use of H1 receptor antagonist

A
  • allergic reactions- hay fever, urticaria, not utilized for bronchial asthma
  • motion sickness- prevention
  • local anesthetic (diphenhydramine and promethazine more potent than procaine)

-antiparkinsonian, anticholinergic, adrenergic blocking, serotonin blocking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Toxicity and drug interactions of H1 receptor antagonist

A

sedation, anti muscarinic (urinary retention), blurred vision

-interacts with cyp450 (inhibition),

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

H2 receptor mediated responses

A
  • secretory in parietal cells (gastric acid secretion)
  • CV system: high doses of histamine- cAMP dep vasodilation and direct stimulation (inc contractility and pacemaker), antagonists have little effect on cardiac function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

H2 receptor antagonists

A

reduce gastric acid secretion- peptic ulcer, gerd, hypersecretory diseases
(do not impact intestinal secretion or oher peripheral H2 receptor mediated effects like HR)

cimetidine, famotidine, nizatidine, ranitidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

H3 receptor mediated response

A

Nervous system- presynaptic receptor modulates NT release

Metabolic effects

thioperamide (also H4 blocker), chlobenpropit, iodophenpropit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Eicosanoids

A
  • Family of oxygenation products of polyunsaturated LCFA

- wide spectrum of biologic activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Arachidonic acid

A

most abundant eicosanoid

  • liberated by phospholipase a2 from glycophospholipids
  • oxidated by COX, LOX (to form leukotrienes), CYP450, and nonezmatic (free radicals)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

COX

A

Convert AA to prostaglandins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

COX1

A

constitutively expressed, widely distributed, houskeeping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

COX2

A

inducible, production of inflammatory molecules
expressed in vascular endothelium (prostacyclin- PGI2)
-renal cox2 essential for normal fxn

19
Q

PGH2

A

Thromboxanes, prostaglandins, prostacyclins are derived from PGH2 (which is derived from AA)

20
Q

Eicosanoid receptors

A

G protein coupled, with cAMP or Ca++ being second messengers

21
Q

PG effect on vasculature

A

TXA2 and PGF2a- vasoconstriction

PGE2 and PGI2-vasodilation (inc cAMP, dec Ca)

22
Q

PG effect on GI tract

A

longitudinal muscle contraction and relaxation of circular muscles. cause colicky cramps
PGE2

23
Q

PG effect on Airway

A

PGE2 and PGI2- relaxation

PDG2, TXA2, PGF2a- contraction

24
Q

Platelets and PGs

A

TXA2 enhances platelet aggregation

25
Q

PGs on Kidney

A

Medulla and cortex synthesize PGs- PGE2 and PGI2
Maintain bp and renal fxn via vasodilation
Regulation of water and electrolyte secretion via COX1 and COX2 products:

  • COX1- promote salt excretion in collecting ducts
  • COX2- increase medullary blood flow and inhibit tubular sodium reabsorption

Loop diuretics have effects in part due to inc cox activity (inhibitors can reduce effect)

26
Q

PGs male reproductive

A

found in semen
PG levels correlate with fertility and enhanced by testosterone

PGE1- enhances penile erection by relaxing smooth muscles in corpus cavernosum

27
Q

PGs- female reproductive

A

PGF2a and low PGE2 promotes uterine contraction

High PGE2 concentration–> relaxation

28
Q

Misoprostol

A

1st and 2nd trimester abortion
oral PGE1

tx of NSAID induced ulcer

29
Q

Dinoprostone

A

PGE2
vaginally for abortion by stimulating contraction of uterus
inducing labor

30
Q

Carboprost

A

PGF2a

contract uterus to control post partum hemorrhage

31
Q

AE of PG on female repro

A

vomiting, fever, diarrhea, bronchoconstriction, altered bp, flushing

32
Q

PG inflammation and immunity

A

PGE2 and PGI2- inc edema and vascular permeability

PGD2 released from mast cells to recruit eosinophils

33
Q

Alprostadil

A

relaxes smooth muscle
PDA, erectile dysfunction, impotence

PGE1

34
Q

Latanoprost

A

PGF1a- topical

tx of open angle glaucoma

35
Q

Dysmenorrhea

A

inc endometrial synthesis of PGE2 and PGF2a

36
Q

Prostacyclin

A

PGI2- inhibits platelets and is a vasodilator

used for pulmonary hypertension because dec pulmonary, peripheral and coronary resistance

37
Q

Tx of pulmonary htn

A

Prostacyclin
Epoprostenol (flushing, headache, hypotension, nausea, diarrhea)-requires continuous IV infusion
Iloprost- inhaled 6-9 times per day
Treprostinil- sc injxn of iv because half life 4 hrs

38
Q

NSAIDs

A

Salicylates- aspirin, salicylic acid
Other- ibuprofen, indomethacin, ketorolac, naproxen, oxaprozin, piroxicam, sulindac
COX2 inh- celecoxib

analgesic antipyretic and antiinflammatory

39
Q

Leukotriene biosynthesis

A

LTC4 and LTD4- potent bronchoconstrictors cause asthma and anaphylaxis
Formed via LOX from AA

40
Q

Leukotrienes in inflammation

A

chemoattractants of eosinophils and monocytes

Proinflammatory mediators of asthma and IBD

41
Q

LTs in heart and smooth muscle

A

cause cardiac depression by reducing myocardial contractility and reducing coronary blood flow
GI- IBD by recruitment of PMNs
Airways- bronchoconstrictors which inc microvascular permeabilit, mucus secretion, chemotaxis of eosinophils

42
Q

Zileuton

A

5-LOX enzyme inhibitor

inhibits leukotriene biosynthesis

43
Q

Leukotriene receptor antagonist

A

Montelukast

given for asthma

IC (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions