What is the primary mechanism by which the drug allopurinol treats gout?

Correct answer: It inhibits xanthine oxidase, preventing the conversion of purines to uric acid.

Explanation

Gout is caused by the accumulation of uric acid crystals. Allopurinol is a substrate analog that inhibits xanthine oxidase, the enzyme responsible for the final steps of purine degradation to uric acid. By blocking this enzyme, it reduces uric acid production and promotes excretion of the more soluble precursors, xanthine and hypoxanthine.

Other questions

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Question 3

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Question 4

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Question 5

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Question 6

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Question 7

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Question 8

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Question 10

What is the key structural feature of the enzyme glutamine amidotransferase?

Question 11

Which statement accurately describes the initial committed step in de novo purine nucleotide synthesis?

Question 12

How do mammals primarily synthesize phosphatidylethanolamine and phosphatidylcholine?

Question 14

What is the role of thioredoxin in the synthesis of deoxyribonucleotides?

Question 15

What is the key difference between the de novo biosynthetic pathways for purines and pyrimidines?

Question 16

How many ATP molecules are consumed in the overall reaction for biological nitrogen fixation to produce two molecules of ammonium ion?

Question 17

What is the source of the five-carbon skeleton for the amino acid proline?

Question 18

What is the role of allopurinol's metabolite, oxypurinol, in the treatment of gout?

Question 19

The drug methotrexate is a potent inhibitor of which enzyme?

Question 20

The disease Lesch-Nyhan syndrome is caused by a genetic lack of which enzyme activity?