Qi ML, Wakabayashi Y, Haro H, Shinomiya K. Changes in FGF-2 expression in the distal spinal cord stump after complete cord transection: a comparison between infant and adult rats.
Spine (Phila Pa 1976) 2003;
28:1934-40. [PMID:
12973137 DOI:
10.1097/01.brs.0000083323.38962.2a]
[Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN
Expression patterns of fibroblast growth factor-2 (FGF-2) in distal transected spinal cord in infant and adult rats were determined by reverse-transcription polymerase chain reaction (RT-PCR) and immunostaining.
OBJECTIVE
To reveal the expression pattern of FGF-2 in distal transected cord of infant and adult rats.
SUMMARY OF BACKGROUND DATA
Descending fibers in the spinal cord of infant and adult rats show different regenerative capacity. One explanation is that different levels of FGF-2, an important neurotrophic factor for promoting neurite outgrowth and repair, are expressed in the distal transected cords of the rats, providing different levels of support for severed axons.
MATERIALS AND METHODS
Spinal cords of infant and adult rats were completely transected. At 12, 24, and 72 hours and at 1 week, segments of distal spinal cord tissues were removed and expression of FGF-2 mRNA was evaluated by RT-PCR. The distribution of FGF-2 and the phenotype of FGF-2-positive cells were determined by immunostaining.
RESULTS
Expression of FGF-2 mRNA was shown to be up-regulated in the distal cord of infant rats but not adult rats. Immunohistochemical analysis showed that neurons in distal cord of infant rats were rich in FGF-2 immunoreactivity (IR), whereas in adult rat neurons FGF-2 IR was hardly observed at all, although a few FGF-2-positive astrocytes were observed in the white matter.
CONCLUSION
After complete spinal cord transection, the expression of FGF-2 in the distal cord of infant rats was high compared with that of adults. This may provide neurotrophic support for axonal extension and functional recovery.
Collapse