Abstract:

BACKGROUND: Many brain injury experiments have demonstrated that improving ischemia and hypoxia in injured tissue helps to promote the recovery of tissue injury and protect neurological function.
OBJECTIVE: To investigate the relationship of endothelial progenitor cells and early neovascularization following spinal cord injury in rats.
METHODS: A total of 60 Sprague-Dawley rats were divided into experimental groups ruined by modified Allen’s method and surgical controls that received laminectomy but did not receive a contusive injury. Peripheral venous blood samples were taken prior to surgery and at 3, 6, 24, 48, 72 and 168 hours after surgery, and the counts of endothelial progenitor cells were determined by flow cytometry. The rats were sacrificed on days 1, 4, 7 and 14. The morphological changes in neovascularization were observed, and the expression of CD31, a marker of vascular endothelial cell, was detected by immunohistochemistry.
RESULTS AND CONCLUSION: The levels of circulating endothelial progenitor cells within the first 3 hours of injury were lower than normal subjects, but increased over time, and reached a peak around 24 hours post-injury at a level that was significantly higher than controls. The change in circulating endothelial progenitor cells was obviously correlated with the change of CD31+ vessels in the region adjacent to the epicenter of the injury site. The results demonstrate a close correlation between an increase in circulating endothelial progenitor cells in response to spinal cord injury and angiogenesis in spinal cord injury rat spinal cord. They also suggest that the increase in circulating endothelial progenitor cells promotes the tissue recovery in spinal cord injury.