Drugs and Receptors Flashcards
define drug
any chemical agent that effects processes in living organsisms
how do most drugs act
stimulation or suppression of biochemical or physiological pathways
Pharmacokinetics
what the biological system ( body) does to the drug
Pharmacodynamics
what the drug does to the biological system ( body)
Therapeutics
use of drugs in treatment of diseases
at what levels of the body can drugs impact
molecule
cell
tissue
system
what is the primary mechanism of action of most drugs
interaction with receptors
define receptor
functional macromolecule to which the drug binds to produce or inhibit biological response
many drugs do not create an effect in the body but do what instead
modulate intrinsic physiological functions
affinity
tendency of drug to bind to receptor
intrinsic activity
ability of drug to initiate cellular response
agonist
binds to and stimulates receptor
antagonist
binds to but does not stimulate receptor
partial agonist
agents that are only partly as effective as agonists no matter the amount employed
inverse agonist
agents that stabilize the receptor in its inactive conformation are termed inverse agonsts
signal tranduction
process by which receptor binding initiates a cascade of biochemical events that lead to a physiological reponse
what are 3 things receptors determine
- quantitative drug use
- selectivity of drug
- mediate actions of pharmacological antogonists
what is key in the receptor for drug-receptor interactions
structure
structure of receptor affects what
affinity
receptor selectivity
chemical functional groups of receptors control what
drug affinity
intrinsic activity
how are receptors classified
effects and potencies of selective agonists/antagonists
what are 2 domains in physiological receptors
ligand-binding
effector-domain
how does ligand binding work
domain are selective
competition for binding spot
how does effector domains work
interact with signal transduction pathways and second messengers
name 3 receptors as enyzmes
protein kinase
protein kinase associated-protein
Guanylyl Cylcase
what attaches to protein kinsases
insulin, growth hromones
what binds protein-kinase associated proteins
cytokines
what binds guanylyl cylcase
atrial natriuertic peptides
ligand-gated ion channels alter what
cell membrane electrochemical potential
cellular composition
what usually binds ligand-gated channels
glutamate
glycine
nicotininc Ach
G-protein-coupled receptors who uses them
hormones, neurotransmitters, amines
G-protein-coupled receptors have what domain
7-membrane spanning helical domain
which subunit of G-protein has the GTP binding site
Alpha
G-protein receptors use what messengers
second messengers
second messenger: cAMP regulates
activates cAMP-dependent protein kinases (PKA)
what does adenylate cyclase do
produce cAMP
second messenger cGMP regulates what and where in the body
PKG
mucosa
vascular smooth muscle cells
second messenger: Calcium is used in what intracellular system
phospholipase C
who generates cGMP
guanylate cyclase
explain transcriptional-related receptors
soluble DNA-binding protein receptors bind to ligand
go to nucleus
what molecules use transcriptional-related receptors
steroids, thyroid hormone, retinoids
Desensitization
down-regulation
continuous stimulation of receptor
example of desensitization
long term administration of agonist
supersensitization
up regulation
chronic reduction of receptor stimulation
example of supersensitization
chronic administration of antagnoist
actions not mediated by receptors
antacids
mannitol
penicillin
