Learning unit: Pharmacodynamics


Impact of the learning unit:

Knowledge of general pharmacological principles is essential for further study of pharmacology and
individual pharmacotherapeutic groups. It makes it easier for students to understand special
chapters in pharmacology, to understand and then to anticipate possible drug interactions at the
level of pharmacodynamics and to estimate possible risks while co-administering drugs.

Important terms

pharmacodynamics

mechanism of action

                specific

                non-specific

                receptor

                non-receptor

receptor theory

                affinity (potency)

                intrinsic activity (efficacy)

receptors

                               according to signal transmission

                                               ligand-gated ion channels

G-protein coupled receptor

receptor kinases

intracellular (nuclear) receptors

                               according to synaptic localization

                                               autoreceptors

homoreceptors

heteroreceptors

ligand

agonist

full

partial

inverse

                               antagonist

antagonism

competitive

non-competitive

reversible

irreversible

chemical

physiologic

allosteric modulation

second messengers

translocation of receptors

up regulation

down regulation

internalisation of receptors

dose

single, daily, maximum daily

threshold, sub-threshold

effective, toxic, lethal

dose-response curves

spare receptors

change in effect after repeated administration

desensitisation

tolerance

tachyphylaxis

rebound phenomenon

synergism

summation, potentiation

one-sided, double-sided


Learning outcomes

Student knows basic types of mechanisms of drug action and explains the receptor theory of drug
action.
Student knows the general principles of drug action at the level of organism, organs and molecular
level.
Student will explain the practical implications of different mechanisms of drug

Student explains the concepts of full, partial agonism and inverse agonism; competitive,
non-competitive, reversible, irreversible antagonism.
Student describes the dependence of the effect of the drug on the dose size, can draw dose-response
curves.
Student explains the types of doses - single, daily, maximum daily, sub-threshold, threshold,
toxic, lethal dose.
Student will describe the function of autoreceptors, homoreceptors and heteroreceptors.
Student knows possible consequences of repeated drug administration - can explain the concepts of
tolerance, tachyphylaxis, up regulation, down regulation, internalisation of receptors.


Study materials:

Rang & Dale's Pharmacology, 8th edition, 2016, chapters 2, 3 and 4

Study materials for courses aVLFA0721p and aVLFA0721c.


Exam questions

General pharmacology: 17. Nonspecific mechanisms of drug action – examples of drugs, 18. Receptor
theory of drugs mode of action, 19. Synergism and antagonism in drug effect (pharmacokinetics,
pharmacodynamics), 20. Dose – response curves, types of doses, drug anamnesis, patient‘s adherence,
21. Specific modes of drug action – target structures, examples of drugs