一般注記Study Design. An experimental study to investigate the in vitro gene expression of neurotrophic factors and receptors in cultured rat spinal cord cells subjected to cyclic mechanical stretch forces. Objective. We evaluated in vitro expression of neurotrophic factors and receptors in cultured rat spinal cord cells under cyclic tensile stress. Summary of Background Data. Application of compressive mechanical stress to the spinal cord results in various changes making it difficult to examine the expression of neurotrophic factors and their receptors. There are no in vitro studies that investigated the biological responses of cultured spinal cord cells to tensile stress. Methods. Spinal cord cells were isolated for culture from 15-day Sprague-Dawley rat embryos. We used the FX3000^〓 Flexercell Strain Unit to induce mechanical stress. We analyzed the effects of mechanical stress on cell morphology, mRNA expression levels of various neurotrophic factors and their immunoreactivities at 0, 2, 6, 12, 24 and 36 hours. Results. Tensile stress for 6 hours resulted in reduction of spinal cord cells and loss of neurites. Cells that survived 24 hrs-stress showed swollen irregular-shaped soma, bleb formation, and fragmented neurites. The cell survival rate decreased while lactate dehydrogenase release increased significantly at 6 hours. There were significant increases in nerve growth factor, brain-derived neurotrophic factor, trkB, p75 neurotrophin receptor (p75^NTR), glial cell line-derived neurotrophic factor, and caspase-9 mRNA expressions during the early period after application of tensile stress. Conclusion. Our results suggest survival of spinal cord neuronal cells under injurious tensile stress with increased synthesis and utilization of several neurotrophic factors and receptors, as well as expression of proteins related to cell apoptosis.
This is not the final published version.
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）