Drug-Receptor Interactions Flashcards
Definiton of: Pharmacokinetics
Effect of body on drugs (absorption, distribution, metabolism and excretion)
Definiton of: pharmacodynamics
effect of the drug on the body (MOA, drug receptor interactions…)
Definiton of: potency
depends on the affinity and the efficacy (intrinsic activity) of the drug.
Definiton of: Affinity
the avidity of the drug (how tightly it binds to the receptor).
Definiton of: Efficacy
the ability of the drug to change the conformation of the receptor once bound to the receptor.
Definiton of: Full agonist
can induce a full response from a tissue.
Definiton of: Partial agonist
can induce only a partial response from a tissue
Definiton of: Selectivity
drugs that interact with receptors have a selectivity for that receptor, however they can stimulate other receptors too in higher concentrations. Drugs are not SPECIFIC they are SELECTIVE
Definiton of: Structure-activity relationship
the relationship between the structure of a drug and the activity of it. Adding a methyl group could change the activity of a drug markedly. Can turn an agonist into antagonists and can also change the pharmacokinetics of the drugs very easily.
What are the 4 drug target sites:
Receptors, ion channels, transport systems, enzymes
What are receptors?
Proteins within cell membranes or in the cytoplasm of the cell.
What are the 4 different types of receptors
Ligand gated channel, enzyme linked receptor, G-protein linked receptor, and intracellular receptor
what are ion channels
selective pores that allow the transfer of ions down the electrochemical gradient
What are the 2 types of ion channels
voltage sensitive (VSSC) and receptor linked/ligand gated ion channels (nAChR)
What are transport systems
transport against concentration gradients (e.g. glucose, ions, neurotransmitters…)
What are the three ways drugs interact with enzymes
enzyme inhibitors (anticholinesterases), false substrates that result in a different final product that is less effective than the natural final product (methyldopa) and prodrugs which interact with enzymes to become active
What happens if you give a partial agonist with a full agonist
means the partial agonist will have antagonist activity as the partial agonist is preventing the full agonist from stimulating a full response
Two types of antagonists?
competitive and irreversible
what bonds do irreversible antagonists form
Covalent
How do you overcome a competitive antagonist
Increase dose of antagonist
