pharmacology Flashcards
what does pharmacology study
how drugs modify
biochemical, physiological and psychological
processes in health and disease
what is pharmacology
Study of the effects of chemical
substances on the function of living systems
what is a drug
chemical that affects physiological
function in specific way
what do drugs generally act on and give examples
target proteins (“receptors”):
➢Enzymes
➢Carriers
➢Ion channels
➢Receptors
what must specificity be
reciprocal: ie specific drug
binds to specific target and specific target will only recognise specific drug
are all drugs specific
no, and so there is always side effects
name 4 types of receptor-effector linkage
- ligand gated ion channels (ionotropic receptors)
- g protein coupled receptors (metabotropic)
- kinase linked receptors
- nuclear receptors
name 4 targets for drug action
receptors, enzymes, ion channels, transporters
what are the 2 stages in drug-receptor interactions
binding, activation
what are the roles of a ligand, agonist and antagonist
the primary ligand activates a receptor (response)
agonist will also activate the receptor (response)
antagonist will block receptor activity (no response)
If: Binding + Activation; what is the drug type
agonist
If: Binding only; what is the drug type
Antagonsit
what is the difference between affinity and efficacy
Ability of drug to bind to receptor = Affinity
Ability of drug to activate receptor= Efficacy
agonist characteristics
has affinity and efficacy
what’s the difference between full& partial agonist
Full agonist –> maximal tissue response
Partial agonist –> submaximal tissue response
antagonist characteristics
has affinity but little or no efficacy
prevents agonist from binding to receptor
Pharmacological experimental Set-up, what is under investigation
tissue under investigation (eg
strip of muscle) mounted in
organ bath
Pharmacological experimental Set-up; what is measured
Effect of drug measured as
biological response (eg muscle
contraction/relaxation)
* Investigate effect of
increasing drug concentration
Pharmacological experimental Set-up; experimental procedure
Set maximum response =
100%, then plot responses at
tested concentrations against
% response
what type of curve is the dose-response curve
sigmoid curve
what happens If agonist and antagonist bind to the same
receptor
the antagonist will act to prevent the agonist from binding
how does competitive antagonism shift the agonist dose response curve
will cause a shift of
the agonist dose response curve to the right without affecting the slope of the
curve
when is the antagonist called ‘surmountable, competitive antagonist’
If increasing agonist concentration reverses
inhibition
what kind of responses do partial agonists produce
produce submaximal response ie they exhibit intermediate efficacy
what exhibits a range of efficacies
chemical series
name 2 parameters agonist potency rely on
affinity and efficacy
