Figure 2.

NaBH₄ and hyaluronidase or chondroitinase increases sensitivity. (A) pSmad cannot be localized without pretreatment, but it is nuclear localized in the prehypertrophic zone (PHZ) and hypertrophic zone (HZ) when treated with NaBH₄ alone. Adding hyaluronidase or chondroitinase alone does not produce a visible signal. NaBH₄ treatment in combination with hyaluronidase or chondroitinase reveals nuclear localized pSmad in the resting zone (RZ) and proliferative zone (PZ). Heparinase II does not increase sensitivity over NaBH₄ alone. (B) Cyclin D1 sensitivity is also increased by NaBH₄ alone or in combination with hyaluronidase or chondroitinase. It is localized to the nuclei of RZ and PZ chondrocytes. (C) Only background fluorescence is visualized without primary antibody. White boxes indicate location where signal is present or expected. Scale bar: in A–C, 200 µm.