NSAIDs Flashcards
name and describe types of nsaids
Aspirin = Unique
Traditional nsaids = Big family, Ibuprofen
Cox 2 inhibitors = Small family, Cox 2 selective = celecoxib
Acetaminophen= Does not act the same way as other nsaids
describe history of aspirin
Plant = chew or swallow
White willow bark = Salix aba, 1828
Leaves of meadowsweet = Spirea ulmaria, 1839
Some pain relief but also SERIOUS side effects
Removed salicin = used to remove pain and fever
describe history of aspirin - 1897
chemist working for drug company
Father had rheumatoid arthritis
Did relieve pain but also GI issues and distress
Chemist made a simple derivative of the molecule here and he put acetyl group on it
=acetylsalicylic acid
Worked - good reilef and less side effects
Name =
A = acetyl
Spir = spirea
In = drug
= ASPIRIN
Felix hofffmann
Sold in 1899
Synthesized at bayer company
Ddint know much about cells
describe what happened in 1971
70 years later = figured out mechanism of action = 1971
ASA blocks prostaglandin synthesis
John vane= English pharmacologist, nobel prize, 1982, aspirin mechanism of action
how do nsaids work
a
how prostaglandins made
Phospholipase frees up arachidonic acid from the cell membrane
= Normal constituent, Arachidonic acid = 20 carbons
Free arachidonic acid acted on by enzymes = cox1 co2 (cyclooxygenases)
= Make prostaglandins
Enzyme sticks cyclic molecule on end of arachidonic acid structure
Why called prostaglandin
Originally isolated from semen
Thought it must be made by prostate gland and only found there but not true
Found all over body
Discovered in human semen, 1930s
describe Features = prostaglandins E2
Unsaturated carboxylic acids
20 carbon skeleton
Cyclohexane ring
Subscript = 2 or 3 indicates double bond
Made by almost all cells
Autocrine and paracrine functions = On cell itself, Cell next door *NOT ENDOCRINE
Rapidly inactivated
what do cyclooxygenases do
make prostaglandins and thromboxanes from arachidonic acid
Subtrate for many different compounds
describe cyclooxygenases
forms ring and adds 2 oxygens
Dimer
Sticks out of endoplasmic reticulum
Arachidonic acid release from membrane
Enters active site
2 active sites on enzyme
Get product = protaglandins
where do nsaids act
G protein coupled receptors
Prostanoids receptors
subgroups = PGD, E, F, I & T
Receptors = DP1, DP2, …, EP1, EP2, … and TP
where do nsaids act- functions
Have different functions
Sometimes opposing functions
Inhibit or activate adenylyl cyclase
Biological effects
Can alter ion channels
Controlling cell motility and other things
what are eicosanoids
(all of the structures formed from 20 carbon initial structure)
describe Diverse effects of eicosanoids
Prostaglandin E receptors =
1-4, When activated = have big effects on cells= Brain,kidney, vascular smooth muscle, platelets
Also synthesis of thromboxanes = involved in handling platelets and blood flow through vasculature
Also prostacyclins have a role in kidney and platelets
describe Prostaglandin synthesis
Fever, renal homeostasis, pain, inflammation, GI cytoprotection (protect stomach lining from gastric acid by increasing mucus secretion)
describe Prostacyclins
pain and inflammation and some kidney and vascular effects
Platelet aggregation
Vasoconstriction
describe eicosanoids - normal vs inflammation
Compounds always have role in normal physiology but increasing synthesis = for pain and inflammation
describe eicosanoids - normal
Semen viability
Intestinal motility
Myometrial tone
Cytoprotection
Bronchial tone
Temperature control
describe eicosanoids - inflammation
Injury and inflammation = synthesis and relative balance has changed
Very important in pathological side of things
Responsible for fever
Asthma
Ulcers = GI problems
Diarrhea
Dysmenorrhea
Inflammation
Bone erosion
Pain
describe cox1
Cox 1= mainly involved in physiological control of things
Constitutive enzyme
Platelet aggregation
Gastric mucosa
Kidney
describe cox2
involved in normal function but mostly induced during injury and inflammation
Inducible enzyme
Pathology = inflammation - Higher level cox2 - Swelling and inflammation and pain and vasodilation
IL 1, TNF induce
Steroids inhibit
what are nsaids valuable in
decreasing pain = analgesic
Inflammation = antiinflammatory
Fever= antipyretic (mild = useful but high fever= bad)
what is pain
Pain → impulse that generates pain goes up into spinal cord = relay and then shoots up through a relay on the thalamus and you are aware of it through connections on cortex
Almost instantaneous
what happens when injured - gen
Sensitive nerve endings all over body
Free nerve endings respond to injury
If injury = immediate release of blood and constituents in injured tissue
what happens when injured - specifics
Releases various prostaglandins
More cells come in from blood and cope with injury
Immediate release prostaglandins
And other things = bradykinin
= stimulate free nerve endings
If prolonged = stimulate nerve endings and impulse goes here =
Synapse in spinal cord
Inflammation to any injury - not mild
Activate macrophages and mast cells
Release all kinds of mediators =
Histamine, prostaglandin, E2, bradykinin, interleukins = Act on receptors
Instantaneous
Nocioceptors = prostaglandins sensitive to other mediators
More serious injury = platelets and thrombosis
what happens when injured - specifics spinal cord
some activity in spinal cord
If noxious problem persists = changes take place in spinal cord
Nsaids can act here
classical signs inflammation
4 classical signs =
Heat
redness = Vasodilation
Swelling = Leakage of vessels
pain
Also may be loss of function
Ex = break bone
describe nsaids for chronic issues
Usually occurs acutely but if have arthritis = happens in multiple joints
Nsaids useful for relieving pain with an acute injury in one place but ALSO relieving pain from chronic issues
describe changes caused by inflammation - gen
reaction of living tissues to injury
Additional cells and mediators from circulation
Pull in mast cells, macrophages, neutrophils
Peripheral nociceptor
Prostaglandin E2 very important here in periphery
Receptors on nerve ending
End result = impulse that travels into spinal cord and goes up into it
describe changes caused by inflammation - longer time
If long problem or significant inflammation = get changes in the spinal cord and further synthesis of prostaglandin E
= increased receptors for prostaglandins on postsynaptic side and on neighbouring internours and on primary afferent fibres
Complicated
Usually action in tissue but also spinal cord to dampen sensation of pain