Delayed nerve repair increases number of caspase 3 stained Schwann cells.
Caspase 3 staining in Schwann cells was investigated with immunohistochemistry, as a measure of Schwann cell apoptosis, after transection and immediate (day 0) or delayed rat sciatic nerve repair (30, 90 and 180 days post injury). Cleaved caspase 3 stained Schwann cells significantly increased at the site of lesion (SNL; median [IQR], 15.2 [7.0] %) and in the distal nerve segment (SND; 9.5 [3.6] %) 10 days after immediate repair. The number of cleaved caspase stained Schwann cells also increased significantly after delayed repair, irrespective of length of delay, at both locations (SNL: 22.0-27.1%; SND: 18.5-22.1%; p<0.05). Some cleaved caspase 3 stained satellite cells were seen in dorsal root ganglia on the injured side, but no stained motor or sensory neurons were observed at any time-point. Delayed nerve repair is associated with more pronounced Schwann cell apoptosis which may explain impaired nerve regeneration after nerve injury and delayed repair.
Saito
Harukazu
H
Department of Orthopaedic Surgery, Murayama Medical Center, National Hospital Organization, Tokyo, Japan.
Kanje
Martin
M
Dahlin
Lars B
LB
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D019771:Axotomy; D053148:Caspase 3 / Q000096:biosynthesis*; D005260:Female; D005727:Ganglia, Spinal / Q000201:enzymology; D007150:Immunohistochemistry; D009416:Nerve Regeneration / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000201:enzymology*; D012584:Sciatic Nerve / Q000293:injuries
D053148:Caspase 3