L2 - How Drugs Act Flashcards
what do protein drugs target
receptors
ion channels
enzymes
carrier molecules
what is specificity in drugs
having a specific binding site
what drug is an exception not going for the regular drug targets
colchicine: inhibits gouty arthritis by binding to tublin and depolymerizes it (drunken walk)
what are receptors
proteins used for chemical communication *chemical messenger)
what does an agonist do
activate the receptor (physiological vs. cascade)
what does an antagonist do
prevent binding to receptor
what is a ligand
anything that binds to the receptor
example of receptors
B-adrenoreceptor (Beta blockers)
what does Noradrenaline do to the heart
increase heart rate (agonist)
what are ion channels
a channel opened by agonist (with binding site)
what does propranolol do to the heart
it treat hypertension (relaxes it) antagonist
what do voltage gated ions allow
they allow ions to flow through when open
what is the effect of anaesthetic on ion channels
they bind and stop ion channel opening (no neurons firing)
what is the effect of benzodiazepine tranqs on the ion channels
they bind to GABA complexes and completely open the channels
when with enzymes drugs act like
a competitive inhibitor
what does fluorouracil do
it replaces uracil in purine (can’t be converted to dTMP) and stops DNA synthesis
what is enzymatic degredation
inactive (prodrug) to active form
what do transporters do
they move ions across membranes
drugs that act as inhibitors to transporters
tricyclic antidepressants/cocaine stop noradrenaline uptake (more leftover)
drugs that act like a false substrate to transporter
amphetamines (meth/MDMA) competes with NA for transport leaving a bunch behind
Amphetamines are
psychomotor simulants: euphoria, excitement, locomotor stimulation, high BP, sleepy, depressed, anxious, hungry
what is a toxicant
harmful substance
what is a toxin
naturally made toxicant
what kind of symptoms can toxicants and toxins cause
primary (directly related) and secondary (indirectly related)
enzymes in toxin are
reversable and irreversible
an example of enzymes in toxins is
acetylcholinesterase inhibition by organophosphate insecticide
receptors/ion channels in toxin
can have agonist or antagonist
some examples of receptors/ion channels in toxin
receptor: nicotine (agonist) curare (antagonist)
ion channel (Na channel): tetrodotoxin, dinoflagellates
what is special about lipid organic solvents like anesthetic
are lipid soluble and can change membrane integrity (toxic), affects membrane proteins
how do the lipid organic solvents change the membrane
they form free radicals and attack the fatty acids
what are toxicants that change DNA called
mutagens
and example of a mutagen
nitrous acid: deletes base portion
deamination: remove amino groups from A/C
alkylating agents (mustard gas): adding alkyl groups
