PHA3801 Lecture Notes - Lecture 17: Tight Junction, Cirrhosis, Degranulation
Document Summary
Pharmacodynamics: mechanism of drug action, describes what the drug does to the body. Understand how drugs exert their effects at the cellular and/or molecular level. Enzyme inhibitor paracetamol (acetaminophen = panadol) Transport inhibitor prozac (fluoxetine = antidepressant) Drug targets: receptors (direct interaction), ion channels, enzymes, transporters. Affinity: the attraction a drug has to a particular receptor (or enzyme) relates to the specific chemical properties or each. Affinity is defined by the dissociation constant the lower the kd, the higher affinity (2). The rate of the forward depends on [d] + [r] Rate of reverse depends on interaction bw d + r. Ka = association constant quantify affinity = [d] that produces 50% of the maximum response at equilibrium, in the absence of receptor reserve. Specificity/selectivity: how well a drug and receptor (or enzyme) bind. Efficiacy: how well a drug produces a therapeutic effect. Potency: measure of how much drug is needed to be efficious.