Analyse the effect of the antagonists on the dose-response curves for both drugs. How would you describe the mechanism of action of the antagonist on the muscarinic receptors?

Data analysis and interpretation Applied Pharmacology

1. Discuss
• What is Acetylcholine and how does it produce contraction of the smooth muscle (dynamics:
receptors, type and drug-receptor interaction)?
• What is pilocarpine  (or carbachol if it was chosen in the experiment) ? what is its mechanism of action? discuss briefly its therapeutic applications
• Identify two drugs that can be used for their effect on smooth muscles within the body (urinary tract, blood vessels, or respiratory system) and briefly discuss the following:
– the mechanism of action
– drug-drug interaction
– therapeutic application

2. Using Excel, or Graphpad Prism:

• Convert the contraction values into %response and the dose into log10 for each drug
• Plot the following graphs :

o the %response vs. log10 dose for acetylcholine (with and without the antagonist, 2 curves in the same graph)
o the %response vs. log10 dose for pilocarpine or carbachol (with and without the antagonist, 2 curves in the same graph)

• Describe both graphs:

o Compare the 2 dose-response curves  (without antagonists): which agonist is the most potent? And which one is the most effective? provide evidence from your data.
o Provide an approximate value of ED50 for both acetylcholine and pilocarpine or carbachol.
o Analyse the effect of the antagonists on the dose-response curves for both drugs. How would you describe the mechanism of action of the antagonist on the muscarinic receptors?