Introduction to Pharmacology

Question 1

Agonist

Answer 1

Drugs that activate receptors/stimulate biological response

e.g. Beta-agonists in Asthma

Question 2

Antagonist

Answer 2

Drugs that block receptors

e.g. Beta-blockers in heart disease

Question 3

Salbutamol

Answer 3

Bronchodilator - Beta2 Adrenoceptor agonist

Drug name for asthma inhalers

Question 4

REWATCH THIS LECTURE

Question 5

How does salbutamol cause bronchodilation

Answer 5

Salbutamol binds to the B2 receptor domain on lung cells which activates the receptor. This collides with the G-protein that causes it to dissociate from the alpha subunit and causes the switching out of GDP for GTP

This alpha subunit binds to the Adenylyl cyclase enzyme and activates it.

This causes it to cycolise ATP into cAMP. cAMP is a messenger that leads to muscular relaxation

Question 6

What curve does an agonist tend to cause in terms of pharmacological response vs concentration

Answer 6

Sigmoidal curve

EC50 is the concentration that causes 50% of maximum response; measure of potency

Question 7

How does a concentration response curve of an agonist change in the presence of a competitive antagonist and non-competitive antagonist

Answer 7

Competitive: Parallel shift to the right

Non-Competitive: Shift to the right and shrinking of curve