Test 2: lecture 22 autocoids 1 Flashcards by jillian Bastidas

what are two amine derived autacoids

histamine
5-Hydroxytryptamine, aka Serotonin

How well did you know this?

Not at all

Perfectly

what are two peptide derived autacoids

angiotensin
bradykinin

How well did you know this?

Not at all

Perfectly

histamine is a major mediator for —

inflammation
anaphylaxis
gastric acid
arousal (awake)

How well did you know this?

Not at all

Perfectly

where can you find histamine in the body

Major storage in specialized vesicles (granules):
* Mast cells (skin, bronchial and intestinal mucosa)
* Basophil granulocytes (blood)
* Enterochromaffin-like cells (stomach mucosa)

How well did you know this?

Not at all

Perfectly

how to make histamine

histidine (L-histidine decarboxylase)→ histamine

How well did you know this?

Not at all

Perfectly

— are antagonists of H1 receptor

pyrilamine
Benadryl (diphenhydramine)
Chlorphen… (Diathal)
Claratin, Zyrtec

histamine receptor found in smooth muscle, endothelial cells and CNS

How well did you know this?

Not at all

Perfectly

— is a antagonist of H2 receptors

ranitidine (zantac)
cimetidine (tagamet)

will cause decreased gastric acid production

Histamine receptor found in gastric parietal cells, cardiac muscle, mast cells and CNS

How well did you know this?

Not at all

Perfectly

— is an agonist of H1 receptor

2-methyl-histamine

histamine receptor found in smooth muscle, endothelial cells and CNS

How well did you know this?

Not at all

Perfectly

— cells in the stomach mucosa can release histamine

Enterochromaffin-like cells

How well did you know this?

Not at all

Perfectly

histamine can be released in response to —

Tissue injury/trauma
Physical agents: heat, cold, (heart burn from cold water), x-rays, etc.
Chemical compounds: (e.g. morphine, tubocurarine
Immunological: IgE → allergy and resistance to parasites).

How well did you know this?

Not at all

Perfectly

histamine released from mast cells will cause what clinical signs

small red spots- local dilation of blood vessels
large red flare
wheal

How well did you know this?

Not at all

Perfectly

histamine will — post capillary venules. Will — permeability of endothelium. mediates attraction of — cells and irriates nerve endings

dilate

increase- allows for edema/swelling

inflammatory cells ( neutrophils, eosinophils, basophiles, monocytes,
lymphocytes)

cause pain/itching

How well did you know this?

Not at all

Perfectly

what antibody does histamine cause allergic reaction

IgE

How well did you know this?

Not at all

Perfectly

what kind of allergic diseases does mast cells play a role in

asthma, eczema, allergic rhinitis, flea allergy dermatitis

How well did you know this?

Not at all

Perfectly

anaphylaxis is a large release of histamine which causes

systemic vasodilation → shock

How well did you know this?

Not at all

Perfectly

which histamine receptor deals with pain and itching

which histamine receptor for sleep-wake cycle

H1 and/or H3

promotes wakefulness

presynaptic H3 receptors will reduce release of — in the brain and peripheral nerves

aCh, amines, peptides

histamine effects on cardiovascular system

will cause vasodilation of aterioles and NO release (which also causes vasodilation) → ↓BP

heart will compinsate by ↑HR

Flushing, sense of warmth, headache (vasodilation)

Urticaria (hives)

what will histamine do in the lungs
what is the exception?

humans and GP: cause bronchostriction (H1)

histamine is toxic to GP

rabbits and other species: bronchodilation (H2>H1)

histamine will do what to the smooth muscle of the GI tract

Guinea pigs/Human: contraction of intestinal smooth muscle- H1

Contraction of guinea pig ileum standard bioassay for histamine.

histamine will do what to smooth muscle of uterus

some species are sensitive and histamine can induce contractions→ abortion

which histamine receptor causes activation of gastric parietal(oxyntic) cells to realease gastric acid

will cause increases production of pepsin, and intrinsic factor

can block with H2 but not H1 antihistamine drugs

H3 agonist will — acid secretion stimulated by food

inhibit

fish poinsoning/ bacterial histamine production will causes

- Flushing - Hypotension - Tachycardia - Headache - Wheals / hives / urticaria - Bronchoconstriction - Gastrointestinal upset Histamine should not be given to asthmatics, patients with active ulcer disease or gastrointestinal bleeding

--- is a physiologic antagnoist to histamine and will cause rapid bronchodilation

epinephrine (EpiPen) acts on different receptors then H1 which cause constriction

--- and --- will inhibit release of histamine

**Cromoglicate, nedocromil**: asthma treatment (Human). **Beta 2 adrenoreceptor agonists** also reduce histamine release

side effects of 1st gen H1 receptor antagonists

drowsiness dry mucous membranes decreased GI motility inhibits muscarinic cholinoreceptor, serotonin, local anaesthetic receptors 1st gen: * Ethanolamines: e.g. diphenhydramine (**Benadryl®**) * Alkylamines: Chlorpheniramine Maleate (diathal) * Ethylaminediamines: e.g. **pyrilamine** (Histall®; H)

--- is often used in small animal practice as H1 receptor antagonist; also acts as serotonin/epinephrine reuptake inhibitor (SNRI), so has mild antidepressant properties

Chlorpheniramine (diathal) has less sedating effect then other 1st gen H1 anatgonists (benadryl)

what are some second gen H1 receptor antagonists?

Cetirizine (Zyrtec®) Loratadine (Claritin®)

why are 2nd gen H1 receptor antagonists less sedative

less lipid soluble, can't get into CNS as easily Loratadine (Claritin®), Cetirizine (Zyrtec®)

H1 receptor antagonists DO NOT block gastric secretion, these are contolled by ---

H2 receptors

H1 receptor antagonists will prevent --- in the lungs

bronchochonstriction should use EPI in emergency, then H1 anathonist

some --- gen H1 antagonist drugs can help with motion sickness / vestibular disturbances / anti-nausea /

1st

what are some H2 antagonists

cimetidine (Tagamet®, prototype) ranitidine Famotidine Pepcid complete nizatidine

H2 blockers can be used to treat

decrease release of gastric acid - duodenal ulcers - uremic gastritis, stress-related erosive gastritis, esophagitis - duodenal gastric reflux →prokinetic effects promoting gastric emptying, GI motility