Pharmacodynamics

Question 1

What is a drug?

Answer 1

Chemical substance of known structure producing a biological effect on a living organism

Question 2

Why would we choose a particular drug?

Answer 2

Depends on the disease/clinical signs
Target area for reduction in symptoms
How the drug interacts with its target
Multitude of drug action following interaction
Dynamics of drug to target interaction

Question 3

What are the actions drugs can take?

Answer 3

Mimic the actions of other molecules e.g. hormones that are normally produced by the body
Inhibit actions of a neurotransmitter etc. in order to reduce an exaggerated response which is detrimental to the animal

Question 4

What are the target molecules of drugs?

Answer 4

Receptors on the cell membrane
Enzymes inside or outside of cells
Ion channels
Transporters in the cell membrane

Question 5

What is an agonist?

Answer 5

A molecule or drug that mimics another molecule binding to create a redponse

Question 6

What is an antagonist?

Answer 6

Competes with molecules and blocks receptors so no response occurs

Question 7

What are the intracellular events that lead to a response within the cell?

Answer 7

Opening of a ligand gated ion channel
Binding to G protein receptor (second messenger system)
Binding to kinase-linked receptor
Binding to nuclear bound receptors

Question 8

What is a biased agonist?

Answer 8

When an agonist binds to receptors it can cause more than one response, a biased agonist will produce more than one response with certain responses being favoured over others