抄録
Tissue regeneration by stem/progenitor cells has been recognized as a maintenance or recovery system of many organs in the adult, and analysis of therapeutic applications for the damaged organs have used ischemic hindlimb or myocardium mostly. Here we examined for new approach that the potential impact of reduced oxygen tension in vivo using a new ischemia model. Direct measurement of oxygen tension allowed its to define three discrete tissue segments with increasingly ischemic microenvironments in nude mice. In this model, a peninsular shaped incision was made dividing epidermis, papillary dermis, and skeletal muscle from the systemic circulation. Following 1 week ex-vivo expansion of endothelial progenitor cells (EPCs) isolated from adult human, EPCs were administrated intravenously into animals for in vivo cell transplantation (n=6). The animal model determined by direct measurements at 4 points were successfully established demonstrating increasingly oxygen tension in ischemic area. The treated animals demonstrated significantly less toe necrosis compared to controls in peripheral perfusion measured by Laser Doppler at day 14. In the measurement of oxygen tension level, the treated animals induce significantly compared to controls in ischemic tissue. Moreover, the ischemic area transplanted EPCs were higher uptake VEGF after cell transplantation compared to controls. In summary, this animal model may be used convenience for analysis of tissue regeneration. [Jpn J Physiol 55 Suppl:S103 (2005)]
