Drug-Receptor Interaction Flashcards
Define pharmacodynamics
The effect of a drug on the body
Define pharmacokinetics
The effect of the body on the drug
What is the role of pharmacodynamics in therapeutics?
Pharmacodynamics causes the positive and negative (toxic) effects of a drug because of interactions with specific cellular target molecules (receptors)
What are the 8 receptor classes?
Enzymes, ionotropic receptors or ion channels, metabotropic receptors, kinase linked and related receptors, nuclear receptors, cytoskeleton or structural proteins, transporters or carrier proteins; nucleic acids, membranes, fluid compartments (non-protein receptors)
How can variation in receptor families allow for multiple types of compounds to have pharmacological consequences?
Many of the receptor subfamilies can be coupled to an executioner or effector that can cause diverse cellular effects
Define Agonist
A drug that activates a receptor
What is a full agonist?
A drug that mimics the physiologic agonist
What is a partial agonist
A drug that activates receptors but is unable to elicit the maximum response of the receptor system
What is an inverse agonist?
An agonist that binds to the same receptor as an agonist but causes the opposite effect
What is an antagonist?
A drug that is unable to trigger receptor activation but physically interacts with the receptor
What is a competitive antagonist?
A antagonist that occupies the receptor and prevents binding of physiological or drug ligands
What is a non-competitive or irreversible antagonist
A drug or physiological compound that covalently binds at the active site of an enzyme and irreversibly inhibits it
What is an allosteric inhibitor
A antagonist that binds at sites other than the active site to cause a conformational change that prevents an enzyme from binding to a physiological substrate
What is the EC50?
The concentration of a drug required to produce 50% of the maximal effect
What is plotted in a drug response curve?
Drug effect (y axis) against logarithm of the dose or concentration (x-axis)
Is a drug more or less potent if it is shifted to the left with the same EC50 on a drug response curve?
More
Does the drug have a greater or lesser maximum efficacy if the curve has a greater response?
Greater
What is the difference between drug potency and efficacy
Efficacy is the effectiveness of a drug and potency is the concentration of a drug that is required to produce 50% of the maximum effect
What does therapeutic index refer to?
The ratio of the toxic dose to effective dose in 50% of individuals. A narrow therapeutic index is with highly potent drugs
Define therapeutic drug monitoring
A narrow therapeutic range may have its dosage adjusted according to the blood levels of the person taking it. For example TDM is used with lithium for bipolar disorder
