Radioautographic and scintillation counting procedures were used to examine the effect of parathyroid hormone (PTH), dibutyryl cyclic-AMP (DB-cAMP), and colchicine on the incorporation of3H-fucose into macromolecular material in organ cultures of bone. Radioautography demonstrated3H-fucose incorporation into bone cells, with the heaviest uptake occurring in osteoclasts. A minimal incorporation occurred in pre-osteoblasts and osteoblasts of the osteogenic periosteum, and in fibroblasts of the fibrous periosteum. PTH appeared to produce a heavier label in association with osteoclasts while decreasing the limited labeling associated with cells of the osteogenic and fibrous periosteum. DB-cAMP and colchicine both markedly reduced the labeling associated with osteoclasts, while the minimal labeling of other bone cells remained. By contrast, scintillation counting results indicated that PTH had little or no effect on3H-fucose incorporation, while DB-cAMP and colchicine considerably reduced the amount of labeled macromolecular material. The incorporation of3H-fucose into glycoproteins and the role of glycoproteins are discussed.
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