Ch 71: Cyclooxygenase Inhibitors: Nonsteroidal Antiinflammatory Drugs and Acetaminophen

Question 1

What is cyclooxygenase (COX)?

Answer 1

The enzyme that converts arachidonic acid into prostanoids.

(p. 849)

Question 2

What are prostanoids?

Answer 2

Prostaglandins and related compounds such as prostacyclin and thromboxane A2.

(p. 849)

Question 3

Describe the role of COX-1.

Answer 3

It is found in practically all tissues, where it mediates many regulatory processes such as protecting gastric mucosa, supporting renal function, and promoting platelet aggregation.

(p. 849)

Question 4

Describe the role of COX-2.

Answer 4

It is produced mainly at sites of tissue injury, where it mediates inflammation and sensitizes receptors to painful stimuli.

(p. 849)

Question 5

Where is COX-2 located and what does it do in each of these places?

Answer 5

In the brain, it mediates fever and contributes to perception of pain. In the kidneys it supports renal function, in the blood vessels it promotes vasodilation, and in the colon it can contribute to colon cancer.

(p. 849)

Question 6

Acid base disturbances result from the effects of aspirin on…
When administered in high therapeutic doses, aspirin acts on the CNS to…

In response, the kidneys…

Answer 6

…respiration.

…stimulate breathing, thus resulting in respiratory alkalosis.
…excrete more bicarbonate. As a result plasma pH returns to normal and a state of compensated respiratory alkalosis is produced.

(p. 849)