Figure 1.
Neuroprotective effects of root reimplantation with fibrin sealant 12 weeks after VRA.
(A and B) Motoneuron cell bodies of the side contralateral to the lesion, (C) Ipsilateral side of VRA-Only, and (D) VRA+Implant. Scale bar = 50 µm. (E) Percentage of neuronal survival after ventral root avulsion and implantation. Note a significant rescue of lesioned neurons in the implanted group. VRA-only was significantly different from implanted group (** p<0.01, n = 5).
Figure 2.
Synaptophysin immunolabeling in spinal cord ventral horn 12 weeks after VRA and reimplantation.
(A and B) Normal synaptophysin immunoreactivity on the contralateral side to the lesion. (C) Ipsilateral side of the lesion in avulsed animals and (D) after root implantation. Scale bar = 50 µm. Observe the preservation of synaptophysin labeling at the surface of the lesioned motoneurons in the implanted group. (E) Quantification of immunolabeling. VRA-only was significantly different from the implanted group (* p<0.05, n = 5).
Figure 3.
Glial fibrillary acidic protein (GFAP) immunolabeling in the spinal cord ventral horn 12 weeks after ventral root avulsion.
(A and B) Normal GFAP immunolabeling on the side contralateral to the lesion. (C) Ipsilateral side of the lesion in avulsion and (D) Reimplantation after avulsion. Scale bar = 50 µm. Observe that ventral root implantation decreased astroglial reaction. (E) The mean ratio of the ipsi-/contralateral integrated intensity of pixels of the ipsilateral and contralateral sides in both groups. VRA-only was significantly different from implanted group (* p<0.05, n = 5).
Figure 4.
Iba1 immunolabeling in the spinal cord ventral horn.
Immunohistochemical analysis of the anterior horn of the spinal cord was labeled with anti-Iba1 12 weeks after injury to assess the degree of microglial reactivity after root avulsion. (A and B) Normal immunolabeling of Iba1 on the contralateral side. (C) Ipsilateral side of the lesion in avulsion and (D) reimplantation after avulsion. Scale bar = 50 µm. (E) The mean ratio of the ipsil-/contralateral integrated intensity of pixels of the ipsilateral and contralateral sides in both groups. No significant differences between groups were observed (n = 5).
Figure 5.
Paw pressure evaluation with the Catwalk system.
The walking track test apparatus: (A) CatWalk machine and (B) an example of a rat at the walkway and the green plantar impression (arrow). In (C), observe a rat from the implanted group using the right paw 12 weeks after injury, whereas the avulsed rat without root repair cannot control the lesioned limb (D), dotted circle indicates the place where the paralyzed paw was supposed to be seen.
Figure 6.
Motor function recovery following ventral root repair with fibrin sealant.
Graph of the peroneal nerve functional index from one to 12 weeks after avulsion of the ventral roots (blue) and followed by avulsion reimplantation of the roots (red). (A) There is an improvement of motor performance in the fibrin sealant implanted group compared to VRA-only from the first week post lesion until the twelfth week (*** p<0.001 and * p<0.05, n = 10, two-way ANOVA followed by Bonferroni post hoc test). There is also an improvement of motor performance in the fibrin sealant implanted group from the first up to the twelfth week after injury (††† p<0.001 n = 10, one-way ANOVA followed by Bonferroni post hoc test). (B) Restoration of weight-bearing capacity following avulsion and reimplantation with the fibrin sealant. Values are expressed as the ratio of ipsi-/contralateral pressure exerted by the paw on the catwalk platform comparing fibrin sealant implanted group to VRA-only from the first week post lesion until the twelfth week (*** p<0.001; n = 10 two-way ANOVA followed by Bonferroni post hoc test). A significant restoration of weight-bearing capacity following avulsion and reimplantation with the fibrin sealant is also observed from the eighth week up to the twefth week, when compared to the first week after injury (††† p<0.001 n = 10, one-way ANOVA followed by Bonferroni post hoc test).
Table 1.
Fold Up- or down-regulation PCR ratio.