Inflammatory Mediators Flashcards
1
Q
storage of histamine
A
- mast cells
- basophils
2
Q
synthesis and release of histamine
A
- in epidermal cells
- gastric mucosa
- CNS
- regenerating or rapidly growing tissues
3
Q
synthesis of histamine from
A
histidine
4
Q
function of endogenous histamine
A
- allergic hypersensitivity response
- gastic acid secretion (by H2 receptors on gastric parietal cells)
- gastric carcinoid tumors (proliferation of mast cells and basophils)
- CNS neurotransmitter
- myenteric plexus
5
Q
endogenous histamine inhibited by
A
- cromolyn sodium
- nedocromil
- moderated by beta-2 agonists
6
Q
what non-immune compounds can release histamine
A
- organic bases
- venoms
- several drugs
7
Q
metabolism of histamine
A
can occur by 2 different pathways:
- N-methyltransferase
- diamine oxidase
8
Q
pharmacologic effect of H1 receptor
A
- vascular/extravascular smooth muscle
- nerves
- glands
- some CNS
9
Q
pharmacologic effect of H2 receptor
A
- vascular/smooth muscle
- gastric parietal cell
- cardiac
- some CNS
10
Q
pharmacologic effect of H3 receptor
A
- CNS
- dampening
- negative feedback
11
Q
pharmacologic effect of H4 receptor
A
WBC
12
Q
effects of histamine on the cardiovascular system
A
- vasodilation
- increased “capillary” permeability
- cardiac stimulation; arrhythmias
13
Q
what is the “triple response” of Lewis (wheal and flare)
A
- Localized red spot
- Brighter red flush/flare
- Wheal that is noticeable in 1-2 mins that occupies the original red spot
14
Q
extravascular effect of histamine
A
- bronchoconstriction
- intestinal smooth muscle contraction
- cause nerve ending pain or itch
15
Q
Histamine Antagonists (ie. Antihistamines) are available as
A
drug block H1 and H2 receptors
16
Q
how are H1 blockers divided
A
- older (1st) generation
- newer (2nd) generation agents
17
Q
2nd generation H1 receptors
A
- penetrate CNS poorly
- are non sedating
18
Q
H2 blockers (OTC) used to deccrease
A
gastric acid secretion
19
Q
what are H1- Receptor Antagonists
A
-REVERSIBLE, competitive inhibitors of the H1 receptor (act like an inverse agonist)
20
Q
1st generation H1 receptors are
A
- sedative
- anticholinergic
21
Q
2nd generation H1 recptors are
A
-less or no sedation
22
Q
what are the properties of H1 receptors
A
- sedation (varies)
- anticholinergic; some with alpha and 5-HT blocking action
- central antinausea and antiemetic effects (some agents irritate GI)
- mild antiparkinsonian effects (anticholinergic)
- local anesthetic effects (structural features of local anesthetics)
- drug allergy from topical administration
23
Q
clinical uses of H1 Antagonists
A
- allergies
- allergic reactions
- pruritus
- itching
- motion sickness
- vestibular disturbances
- OTC sleep aid
24
Q
function of H2 Receptor Antagonists
A
block histamine - induced gastric acid secretion
25
H2 receptor antagonists have a larger effect on
nocturnal acid secretion
26
all drugs in H2 receptor antagonists are available OTC to reduce
gastric acid secretion
27
name 4 H2 receptor antagonists
1. cimetidine
2. ranitidine
3. famotidine
4. nizatidine
28
function of cimetidine
inhibits p450 and may cause confusion in ELDERLY patient receiving larger doses
29
what are kinins
are peptide autocoids that act locally to produce pain, vasodilation, increased vascular permeability
-synthesize vasoactive substances (ie. prostaglandins)
30
kinins are activated by
- tissue damage
- allergic rxns
- viral infection
- inflammatory events
31
kinins are cleaved from
alpha 2 globulins (kininogens)
32
bradykinin and kallidin are cleaved by
plasma or tissue kallikrein
33
plasma killikrein activated by
factor XII
34
kinins are inactivated by
- ACE (kininase II)
| - inactivated by conversion to active Des-Arg metabolites by other peptidases
35
bradykinin and kallidin are cleaved from
- HMW or LMW kininogens by plasma
| - tissue kallikrein
36
B1 (kinin receptor) binds to
des-Arg metabolites
37
B1 (kinin receptors) are present in what cells
normal vascular smooth m.
38
B1 (kinin receptors) are unregulated during
inflammation by cytokines, GF and endotoxins
39
function B2 (kinin receptors)
- mediate the effects of bradykinin in the absence of inflammation
- activate proinflammatory transcription factors, NO synthesis, prostaglandin synthesis
40
pharmacological function of kinins
- pain
- inflammation - increase permeability
- respiratory disease - provokes bronchospasms
- kidney function - regulate urine volume and composition
41
drugs affecting kinins
- ACE inhibitors
- investigational bradykinin agonists and antagonisists
- kallikrein inhibitors
42
what are eicosanoids
- prostaglandins
| - leukotrienes
43
eicosanoids are derived from
20-C essential F/A that contain 3,4 or 5 double bonds
44
where are eicosanoids found
in almost every tissue and body fluid
45
eicosanoid production increases in response to
diverse stimuli
46
what are the 2 routes of metabolism of arachidonic acid
1. lipoxygenase
| 2. cyclooxygenase
47
lipoxygenase pathway leads to
HPETEs
HETEs
leukotrienes
48
cyclooxygenase pahtway leads to
- cyclic endoperoxides (PGG and PGH)
| - metabolic products
49
how many active sittes does cyclooxygenase have
2
50
expression of cyclooxygenase-1 (COX-1)
constitutively expressed
51
where is COX-2 expressed
- endothelial cells
- kidney
- brain
52
COX-2 induced by
- cytokines
- GF
- endotoxin
- an effect that is blocked by glucocorticoids
- laminar shear force
53
function of eicosanoids
- inflammation
- smooth muscle tone
- hemostasis/thrombosis
- paturation (labor delivery)
- gastrointestinal secretion
- renal function
54
what blocks Eicosanoids
NSAIDs
55
what drugs decrease the effect of leukotrienes
Leukotriene receptor antagonists
| 5-Lipoxygenase inhibitor
56
Name the Leukotriene receptor antagonists
1. Zafirlukast
| 2. Montelukast
57
name the 5-Lipoxygenase inhibitor
zileuton
58
what is zileuton used to treat
- asthma
| - block leuoktriene derivatives
59
what are the effects of Eicosanoids on the Cardiovascular system
- vasodilate (PGI2, PGE2, PGD2)
- hypotension (LRC4, LTD4)
- vasoconstrict (TXAs, PGF2; endoperoxides)
- increase C.O (PGE2m PGF2)
- increase capillary permeability (LTC4, LTD4)
60
what are the effects of Eicosanoids on Blood Elements
- platelet aggregation (PGI2 inhibits; TXA2 promotes)
- chemotaxis (LTB4)
- inhibit lymphocyte function (PGE2)
61
postaglandins contract or relax what type of muscle
extravascular smooth muscle
62
leukotrines contract what kind of muscle
smooth muscle
63
broncoconstriciton caused by
LTC4
LTD4
PGF2
PGD2
64
uterine contraction caused by
PGE2
| PGF2
65
gastrointestinal smooth muscle contraction caused by
LTC4
LTD4
PGE2
PGF2
66
effect of prostaglandins on GI
- decrease gastric secretion
- increase mucus
- promote local blood flow
- stimulate epithelial growth (PGE2 PGI2)
67
effect of prostaglandins on kidney and urine formation
- increase renal blood flow
- decrease chloride reabsorption
- increase renin secretion
68
affects of prostaglandins on afferent nerves
- direct pain producer
| - hyperalgesia
69
effect of prostaglandins on CNS
- elevate body temp
| - modulate NT
70
effect of prostaglandins on eye
PGF decrease intraocular pressure
71
what are the therapeutic uses of prostaglandins
- cervical ripening (PGE2)
- therapeutic abortion - stimulate uterine contraction)
- gastric cytoprotection (Misoprostol; PGE1 analog)
- maintenance of patent ductus arterioles
- primary pulmonary hypertension
