Figure 5.

Representative gel electrophoresis of the GAGs extracted from the articular cartilage after NOS inhibitors or UA administration in zymosan arthritis. Zymosan was injected i.art. into both knee joints and the articular cartilage damage was evaluated by measuring its GAG content at 7 or 14 days after zymosan. L-NAME (25 mg kg⁻¹) or AG (50 mg kg⁻¹) was injected 30 min before zymosan and daily, until sacrifice, at 7 days. UA (100 mg kg⁻¹ i.p.) was injected 30 min before zymosan and four times daily, until sacrifice, at 14 days. GAG content in extracts was determined by densitometry (525 nm), using the standards for comparison. M – standard GAG mixture with 5 μg containing equal amounts of C4, C6, and HS; C – animals that received only saline i.art.; ABC – sample from C animals that was subjected to enzymatic digestion using chondroitinase ABC; NT – animals that received saline (i.p.) after zymosan injection killed 7 days later; L-NAME 25 – animals treated with L-NAME (25 mg kg⁻¹ i.p.) and killed 7 days after zymosan injection; AG 50 – animals treated with AG (50 mg kg⁻¹ i.p.) and killed 7 days after zymosan injection; UA 100 and UA 250 – animals treated with with UA (100 or 250 mg kg⁻¹ i.p.) and killed 14 days after zymosan injection, respectively.