We investigated the expression of vascular endothelial growth factor (VEGF) and its receptors (Flt-1 and KDR/Flk-1) during muscle regeneration by immunohistochemistry and real-time RT-PCR. On days 5 and 7 after the induction of injury, VEGF and Flt-1 were detected in the cytoplasm and KDR/Flk-1 in the cytoplasm and on cell membranes of the same regenerating muscle fibers. The levels of these proteins in the regenerating muscle fibers gradually decreased until day 20. In contrast, these proteins were not detected in the fibers of normal muscle. This suggests that regenerating muscle fibers express VEGF and its receptors in response to injury. In addition, we found that the VEGF mRNA transcript transiently increased after 12 h of muscle injury and then returned to the basal levels observed in normal muscles on day 1. The expression of Flt-1 and KDR/Flk-1 mRNA transcripts also peaked on day 3 and then returned to the basal levels observed in normal muscles on day 10. These findings suggest that regenerating muscle fibers are an important source of VEGF and that VEGF signaling through Flt-1 and KDR/Flk-1 may be involved in the process of muscle regeneration in vivo.
- MeSH
- Gene Expression physiology genetics MeSH
- Financing, Government MeSH
- Immunohistochemistry methods utilization MeSH
- Data Interpretation, Statistical MeSH
- Muscle, Skeletal physiology growth & development MeSH
- Mice anatomy & histology physiology growth & development MeSH
- Reverse Transcriptase Polymerase Chain Reaction methods utilization MeSH
- Receptors, Vascular Endothelial Growth Factor genetics MeSH
- Vascular Endothelial Growth Factor A physiology MeSH
- Animals MeSH
- Check Tag
- Mice anatomy & histology physiology growth & development MeSH
- Animals MeSH
- Publication type
- Comparative Study MeSH
