Feza Korkusuz1, Petek Korkusuz2, Aykut Özkul3

1Medical Center, Middle East Technical University, Ankara
2Department of Histology and Embryology, Hacettepe University, School of Medicine, Ankara
3Department of Virology, Ankara University, Faculty of Veterinary Medicine, Ankara

Keywords: Cells, cultured; bone development/physiology; fibroblasts; osteogenesis; periosteum; substance P.

Abstract

Objectives: Substance P (SP) is a neuromediator that influences development, growth, and formation of bone. Substance P receptors have not been specified on osteoblast-like cells. It is assumed that the neural network within the periosteum may be the site of neuroendocrine control mechanism of bone growth and repair. The aim of this study was to identify SP receptors on fibroblast-like cells derived from the periosteum. Materials and methods: Fibroblast-like cells were derived from the periosteum of six patients who underwent femoral derotation and shortening osteotomy for developmental dislocation of the hip. Periosteal tissue was removed from the osteotomy site and the cells were suspended in cell culture media and grown on 24-well macroplates. Polyclonal SP antibodies were added and anti-rabbit peroxidase conjugate (whole molecule) was used as a second antibody. SP reactive sites on cell surface were screened by addition of substrate (3-amino-9-ethyl carbazole+dimethylformamide + 3% hydrogen peroxide). Surface and/or intracellular staining was evaluated under microscope.
Results: Fibroblast-like cells showed immunostaining for SP receptors. The presence of SP-sensitive binding sites were identified on fibroblast-like cells derived from the periosteum.
Conclusion: Substance P receptors shown on fibroblast- like cells derived from the periosteum are very likely to have a modulating effect in periosteal bone growth and healing.