Abstract: Objective To observe the glycosaminoglycan effects of glucosamine (GS), chondroitin sulfate (CS) and combination of the two compounds on histopathological and histochemical features and glycosaminoglycan (GAG) content of cartilage of female Hartley guinea pig in vivo. Methods One hundred and twenty guinea pigs at 2 months of age were randomly distributed into 3 test groups plus a control group. Four groups were designed in the research including control group (Control group: distilled water), GS group (0.5%GS ), CS group (0.25% CS) and GS-CS combination group (0.5%GS+0.25%CS). After 5 months of administration, HE dye, PAS dye, Alcian Blue dye, Mallory dye and GAG contents were performed and measured on articular cartilage of Hartley guinea pigs. Results During the entire 5 months period, distinct pathological lesions appeared just after the first month in control group, and the distinct pathological lesions didn't appear until the third month ended in GS group. In CS group, moderate pathological lesions were observed in the fourth month, while there were almost no obviously pathological changes in combined group during the whole test period. After 2 months of treatment, GAG contents of all tested groups decreased, but from the 3^rd month, GAG contents of GS, CS and GS-CS groups increased again. Compared with the control group, GAG contents of GS, CS and GS-CS groups were different in the first 2 months (P<0.05). GAG contents of GS and GS-CS groups were significantly different in the 3^rd month (P<0.01), After 4 months, GAG contents of all tested group increased again, significantly different with the control group (P<0.01). Conclusions GS, CS and combination of the two compounds can improve the growth of articular cartilage of Hartley guinea pigs and delay the degeneration of articular cartilage. Especially the united treatment of GS and CS was the most strong, then the intensity of GS. CS was much weaker than GS and the united treatment of GS and CS.

Key words: GS, CS, Hartley guinea pig, Cartilage, GAG