1. Pharmacology UG-Course
Touqeer Ahmed PhD
19th February, 2015
Atta-ur-Rahman School of Applied Biosciences
National University of Sciences and Technology

2. Basic Concepts in Pharmacology
Pharmacodynamics: is the study of the biochemical and physiological effects of drugs on the body or on microorganisms or parasites within or on the body and the mechanisms of drug action and the relationship between drug concentration and effect.
Pharmacokinetics: is the study of what the body does to a drug

3. Basic Concepts in Pharmacology
Protein targets for drug binding
Four main kinds of regulatory protein are commonly involved as primary drug targets, namely:
1.receptors (activate signaling pathways) 3.enzymes
2. carrier molecules (transporters) 4.ion channels.
Agonists and antagonists
Agonists, which 'activate' the
receptors, and antagonists,
which combine at the same site
without causing activation,
and block the effect of agonists
on that receptor.

4. Basic Concepts in Pharmacology
THE BINDING OF DRUGS TO RECEPTORS
Why do we plot it on the Log scale?

5. Agonists (Quantifying Agonism)
Drugs have two observable properties in biological systems:
Potency
Potency is controlled by four factors:
Receptor density in a tissue
Efficiency of the stimulus-response mechanisms present by default in the tissue
Affinity of the drug for its receptor
Efficacy
Efficacy/Magnitude of effect (when a biological response is produced)
The advantage of using efficacy is that this property depends solely on efficacy, whereas potency is a mixed function of both affinity and efficacy

6. Antagonism
Antagonists are drugs that decrease or oppose the actions of another drug or endogenous ligand.
An antagonist has no effect if an agonist is not present.
Antagonism may occur in several ways. Many antagonists act on the identical receptor macromolecule as the agonist. Antagonists, however, have no intrinsic activity and, therefore, produce no effect by themselves.
Although antagonists have no intrinsic activity, they are able to bind avidly to target receptors because they possess strong affinity.