Effect of bupivacaine on muscle tissues and new bone formation induced by demineralized bone matrix gelatin

The contribution of different cell lineages to bone repair: exploring a role for muscle stem cells

An anabolic response driven by osteoblasts is critical for the process of bone healing. Current evidence suggests that these osteoblasts may arise from multiple tissue types and cell lineages. Stem cells present in the bone marrow, periosteum, local soft tissues, vasculature, and/or circulation have been shown to have osteogenic potential. Transplanted cells from these sources have also been shown to incorporate into induced ectopic bone or repaired bone. While these experiments demonstrate the latent capacity of different lineages to assume an osteoblastic phenotype under pro-osteogenic conditions, the actual contribution of the different lineages to various repair situations in vivo remains unclear. This review explores the data arising from different bone formation and repair models. We propose a model suggesting that cells arising from the local tissues, particularly muscle cells, may play an important role in fracture repair under situations where the periosteal and/or bone marrow progenitor populations are depleted.

Effect of 1-hydroxyethane-1,1-diphosphonic acid (HEDP) on new bone formation induced by bone matrix gelatin (BMG)

The effect of the biphosphonate 1-hdroxyethane-1,1 diphosphonic acid (HEDP) on induced ectopic osteoneogenesis was studied by light and electron microscopy. Demineralized bone matrix gelatin (BMG) was implanted into the rectus abdominis muscle of 8-week-old Sprague-Dawley rats, HEDP was administered subcutaneously with a mini-osmotic pump, and histological changes were examined 4 days, 1, 2 and 3 weeks later. Four days after implantation, "acellular mineral deposition" in the control group was suppressed in the HEDP group. Two weeks after BMG implantation, cartilage formation was more intensive in the HEDP-treated group than in the control group. Three weeks after implantation, new lamellar bone with bone marrow was observed in the control group, while immature osteoid tissue detected by type II collagen in the central area was prominent in the HEDP-treated group. HEDP-treatment also suppressed the appearance and activity of osteoclast-like cell.