In osteoarthritis, what is the effect of the disruption of the pumping action of proteoglycans?
A)Pump malfunction stimulates the induction of nitric oxide synthase (iNOS) and nitric oxide (NO), which degrades the cartilage.
B)Cartilage is damaged by proteolytic enzymes because they cannot be pumped out of the joint.
C)Cartilage becomes dry, brittle, and wears away because fluid cannot be pumped into the cartilage.
D)Cartilage takes in too much fluid and is unable to withstand the stresses of weightbearing.

Question

Quizplus · Accepted Answer

Changes in the conformation of proteoglycans disrupt the pumping action that regulates movement of water and synovial fluid into and out of the cartilage. Without the regulatory action of the proteoglycan pump, cartilage imbibes too much fluid and becomes less able to withstand the stresses of weightbearing.

In Osteoarthritis, What Is the Effect of the Disruption of the Pumping