Unit 9 Drugs

Question 1

Describe the MOA of esomeprazole

Answer 1

Esomeprazole : Brand name = Nexium
Class = Proton pump inhibitor
Chemistry: Small molecule, Bound to plasma proteins in the blood

Pharmacology:
Ligand = esomeprazole
Activity = Irreversible Inhibitor of H+, K+-ATPase enzyme
Target = H+, K+-ATPase enzyme ( α, β-heterodimeric protein) within secretory canaliculus of the parietal cell

Physiology: = Esomeprazole binds to the sulfhyrdl groups of cystine amino acids present on the H+, K+-ATPase enzyme of gastric parietal cells
This inhibits the function of the H+, K+-ATPase enzyme
Inhibits gastric acid secretion

Clinical indications: Commonly used to treat acid reflux disorders such as GERD + peptic ulcer disease. In this case it is used in conjunction with naproxen to relieve the symptoms of rheumatoid arthritis.

Question 2

Describe the MOA of amoxicillin

Answer 2

Binds and hence inhibits penicillin binding protein 1 produced by the helicobacter pylori bacterium
This inactivates transpeptidase enzyme preventing cross link formation between peptidoglycan strands
Bacterial wall synthesis is inhibited

Question 3

Describe the MOA of clarithromycin

Answer 3

Macrolide
Binds to the 23 S rRNA of the 50s subunit of the bacterial ribosome
Prevents translocation of aminoacyl tRNA and polypeptide synthesis