Histamine, Serotonin, and the Ergot Alkaloids Flashcards
1
Q
hormone or chemical produced by the body that acts locally to exert a biological effect
A
autoacoid
2
Q
important mediator of immediate allergic and inflammatory reactions
A
histamine
3
Q
modest role in anaphylaxis
A
histamine
4
Q
formed by decarboxylation
A
histamine
5
Q
either stored in granules or rapidly inactivated by 2 enzymes
- monoamine oxidase
- diamine oxidase
A
histamine
6
Q
stored in mast cells (tissues), basophils (blood), enterochromaffin cells of the gut, and some neurons
A
histamine
7
Q
which is an autoacoid?
A
histamine
8
Q
precursor of histamine
A
histidine
9
Q
2 enzymes that breaks histamine down?
A
monoamine oxidase and diamine oxidase
amine is in them- from histAMINE
10
Q
histamine release is by :
A
Immune
Chemical
Mechanical
11
Q
Most important pathohysiological mechanism of histamine release from __ and __ cells
A
mast cells and basophils
12
Q
Sensitization of mast cells and basophils with __ causes rapid DEGRANULATION
A
IgE
13
Q
degranulation of mast cells and basophils are dependent on what ___
A
Calcium and Energy Dependent
14
Q
the immune release of histamine can exert a negative feedback through __ receptors
A
H2
15
Q
what chemicals can cause histamine release?
A
morphine and tubocurarine
16
Q
t/f chemical release of histamine is not dependent on energy or mast cell granulation
A
true
17
Q
mast cell injury can cause degranulation and release is an example of what type of histamine release?
A
mechanical
cell wall is being destroyed so the cell’s goodies are being released
18
Q
how many receptor subtypes of histamine are there? how many do we care about?
A
4, 2
19
Q
Histamine subtypes receptor that mediates allergic rhinitis
A
H1
20
Q
Histamine subtype receptor that mediates stomach acid production
A
H2
21
Q
Gq coupled receptor that increases IP3 and DAG formation, histamine
A
H1
22
Q
Gs coupled receptor that increased cAMP and PKA activity, histamine
A
H2
23
Q
Gi coupled receptor, decrease in cAMP
A
H3 and H4
24
Q
Histamine subtype that is in the SM, endothelium and brain
A
H1
25
Histamine subtype that is in the Gastric mucosa, cardiac muscle, mast cells and brain
H2
26
stimulation of sensory nerve endings, causes pain and itching via ___ stimulation - nervous system effects
H1
27
histamine will cause tachycardia with decrease of blood pressure, this is caused by __
vasodilation via H1 receptors
28
vasodilation of H1 receptors is caused by __ production of NO in the endothelium
increased
29
what causes separation of endothelial cells in the microcirculation? permits fluids and small proteins to escape to the perivascular space, this is responsible for hives and the hallmark of histamine release in the skin
edema
30
t/f asthmatics are more sensitive to histamine than nonasthmatics.
true - this is how you can test for asthma!
31
histamine has what kind of effect on the GI SM?
contraction - LARGE doses may cause DIARRHEAAAAAA
32
t/f histamine may induce contractions during anaphylaxis and cause abortion
t, so sad
33
histamine stimulates gastric acid secretion via __ receptors
H2
34
what is characteristics red spot, edema, and flare responses to intradermal histamine administration?
triple response
35
CNS effect of histamine?
nociception
36
smooth muscle actions opposite to histamine, used to counteract the effects of histamine during anaphylaxis
epinephrine
37
also known as mast cell stabilizers
release inhibitiors of histamine antagonism
38
prevent the degranulation of mast cells
release inhibitiors of histamine antagonism
39
used in the treatment of asthma
release inhibitiors of histamine antagonism
40
cromolyn and nedocromil are in what section?
release inhibitiors of histamine antagonism
41
antagonists for __ and __ are readily available (OTC) and are of the great therapeutic benefit
H1 and H2
42
Antagonists of __ and __ are not available for clinical use and are POINTLESSSSS
H3 and H4
43
What do you have to take for days before you see a response, dont work acutely?
Cromolyn and Nedodromil
44
what group of histamine antagonists are in generations?
H1 and First & Second generation
45
__ generation is generally less selective for H1 Receptors and is associated with the majority of the side effects
first generation
46
more selective for H1 receptors and dont cross the BBB
second generation
47
prevent motion sickness but dont treat preexisting motion sickness is a side effect of what class of drugs?
first generation of h1 antagonists
48
h1 antagonists - antiparkinsonism effect drug, suppress extrapyramidal symptoms of antipsychotics
diphenhydramine
49
sedation, urinary retention, dry mouth and blurred vision are effects of what class of drugs
first generation of h1 antagonists
50
may cause orthostatic hypotension - what side effect of first generation of h1 antagonists
antiadrenegic effects
51
used to treat serotonin storm
cyproheptadine
52
Name the side effects of h1 antagonists first generation
```
Sedation
Antiemetic effects
Antiparkinsonism effects
Anticholinogic effects
Antiadrenergic effects
Antiserotonergic effects
Local anesthesia
```
53
anticholingeric activity and marked sedation is a characteristics of what generation of h1 antagonists
first generation h1 antagonists
54
clinical uses of antihistamines
allergic reactions
motion sickness
nausea and vomiting associated with pregnancy
gastric acid secretion
55
some second generation drugs are metabolized by ___
cyp3a4
56
"jack of all trades" neurotransmitter, gut hormone, platelet activator and migraine mediator
serotonin
57
synthesized from L-tryptophan
serotonin
58
metabolized by monoamine oxidase then aldehyde dehrydogenase to 5-hydroxyindoleacetic acid
serotonin
59
24 hour urinary 5-HIAA levels can be used to assess ___ production
serotonin
60
brain __ neurons involved in: mood, sleep, appetite, thermoregulation, perception of pain, blood pressure, vomiting, depression, anxiety and migraine
serotonin
61
precursor of melatonin
serotonin
62
produced in pineal gland and promotes sleep
melatonin
63
5-ht3 receptors present in medullary center governing __
vomiting
64
__ receptors in afferent vagal nerve endings associated with chemoreceptors reflex
5ht3
65
powerful activator of sensory nerve endings involved in pain and itch of stings
serotonin
66
small bronchoconstrictive effect, may cause hyperventilation
respiratory effect of serotonin
67
vasconstrictor in vascular smooth muscle with intact endothelium, vasodilator in skeletal muscle and heart, can elicit bradycardia due to chemoreceptor reflex
cardiovascular effect of serotonin
68
triphasic blood pressure response upon ___ of serotonin
injection
he emphasized this route
69
decreased HR, CO, BP dur to chemoreceptors
Increased in BP due to vasoconstriction
Decrease in BP due to vasodilation
triphasic blood pressure response after injection of serotonin
70
serotonin promotes platelet aggregation via __
5ht2
71
powerful stimulant of GI smooth muscle that promotes peristalsis
GI tract effect of serotonin
72
typically results from the combination of MAOI inhibitors and serotonin antagonists or SSRI's, ranges mild to severe
serotonin syndrome
73
Presents as hyperthermia, hyperreflexia, tremor, clonus, hyperactive bowels, diarrhea, mydriasis, agitation and possible coma
serotonin syndrome
74
Treatment of serotonin syndrome
cyproheptadine
75
5HT1 antagonists first generation but also blocks 5HT2 Receptors
cyproheptadine
76
5HT1A agonist, nonbenzodiazepine anxiolytic
BUSPIRONE
77
d-enantiomer of fenfluramine, a component of Fen-Phen
DEXFENFLURAMINE
78
Appetite suppressant that was withdrawn from market
DEXFENFLURAMINE
79
prototype of triptans
sumatriptin
80
5HT1D/1B agonists
triptans
81
used from acute migraine treatment and cluster headaches
triptans
82
5HT2C agonist, appetite suppressant
LORCASERIN (BELVIQ)
83
5HT4 agonist, treatment of GERD, restricted use due to toxicity
CISAPRIDE
84
5HT4 partial agonist, irritable bowel syndrome
TEGASEROD
85
SM manifestations of carcinoid tumor and cold induced urticaria
CYPROHEPTADINE
86
significant alpha 1 adrenoceptor blockage = hypotension
KETANSERIN
87
no alpha adrenoceptor activity, antiplatelet activation
RITANSERIN
88
5HT2 antagonists
tanserins
89
5HT3 antagonists
setrons
90
prototype of setrons - 5-HT 3 antagonists
ondansetron
91
prevents nausea and vomiting associated with chemotherapy
ondansetron
92
compounds found commonly in nature, fungi
ergot alkaloids
93
have been ingested for thousands of years, epidemics of ergotism or ergot poisoning
ergot alkaloids
94
St. Anthony's fire
Ergotism
95
Symptoms include dementia with vivid hallucinations, prolonged vasospasm that could cause gangrene, uterine contraction that can result in abortion, nausea, vomiting, diarrhea
ergotism
96
classic example of ergot poisoning
LSD
97
behavioral effects via pre and post synaptic 5-ht2 agonism
cns effect of ergots
98
extrapyramidal motor control, agonism at ___ receptor for ergot effects
dopamine
99
regulation of pituitary prolactin release via pituitary dopamine receptor agonism, effective treatment for ___
prolactinemia
100
agonist and partial agonist effects at ___ receptors, can cause epinephrine reversal
alpha adrenoceptors
101
severe and prolonged vasospasm upon OD
vascular smooth muscle effects of ergots
102
used to induce labor by working on uterine smooth muscle
ergots
103
causes nausea, vomiting, diarrhea at even low doses
ergot effect on GI tract
104
systemic effects of ergots
CNS
Vascular SM
Uterine SM
GI tract
105
clinical uses of ergots
Migraine
Hyperprolactinemia
Postpartum hemorrhage
106
contraction is unlike natural labor, never give before delivery
postpartum hemorrhage use of ergots
107
second line to oxytocin to control postpartum bleeding
ERGONOVINE
108
usually effective in 1-5 minutes, usually given during placental delivery or immediately afterward if bleeding is significant
ergonovine
109
reduces high serum prolactin levels associated with pituitary tumor
BROMOCRIPTINE
110
similar to bromocriptine but more potent
CABERGOLINE
111
favored by some clinicans over ergotamine
DIHYDROERGOTAMINE
112
most clinicans prefer the triptans but ergotamine can be effective when given during the ___ of the attack of a mirgraine
prodrome
113
often combined with caffeine to speed its absorption
ergotamine
114
vasoconstriction can be prolonged and cumulative, no more than 6mg/attack and 10 mg/week
ergotamine
