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Retrograde tracing and toe spreading after experimental autologous nerve transplantation and crush injury of the sciatic nerve: a descriptive methodological study.

van Neerven SG, Bozkurt A, O'Dey DM, Scheffel J, Boecker AH, Stromps JP, Dunda S, Brook GA, Pallua N - J Brachial Plex Peripher Nerve Inj (2012)

Bottom Line: In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading.After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively.No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals.In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Plastic Surgery, Reconstructive and Hand Surgery, Burn Center, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany. svanneerven@ukaachen.de.

ABSTRACT
Evaluation of functional and structural recovery after peripheral nerve injury is crucial to determine the therapeutic effect of a nerve repair strategy. In the present study, we examined the relationship between the structural evaluation of regeneration by means of retrograde tracing and the functional analysis of toe spreading. Two standardized rat sciatic nerve injury models were used to address this relationship. As such, animals received either a 2 cm sciatic nerve defect (neurotmesis) followed by autologous nerve transplantation (ANT animals) or a crush injury with spontaneous recovery (axonotmesis; CI animals). Functional recovery of toe spreading was observed over an observation period of 84 days. In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading. After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively. No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals.In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing. The present findings demonstrate that a multimodal approach with a variety of independent evaluation tools is essential to understand and estimate the therapeutic benefit of a nerve repair strategy.

No MeSH data available.


Related in: MedlinePlus

Retrograde tracing - α-motor neurons: Images of ANT (A) and CI (B) lumbar spinal cord containing retrograde traced α-motor neurons. Quantification of positively traced neurons revealed no difference in the amount of labelled α-motoneurons between ANT and CI animals (C). Total amount of positively traced motor neurons was counted in lumbar spinal cord segments L3-L6 (D).
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Figure 2: Retrograde tracing - α-motor neurons: Images of ANT (A) and CI (B) lumbar spinal cord containing retrograde traced α-motor neurons. Quantification of positively traced neurons revealed no difference in the amount of labelled α-motoneurons between ANT and CI animals (C). Total amount of positively traced motor neurons was counted in lumbar spinal cord segments L3-L6 (D).

Mentions: Retrograde tracing with DiI was used to evaluate structural aspects of sciatic nerve regeneration. Representative images and quantification of positively labelled neurons in the spinal cord and DRGs are shown in Figures 2 and 3. Longitudinal sections of the ventral columns revealed positively labelled perikarya in the spinal cord ipsilateral to the lesion site. Logically, α-motor neurons of the contralateral side (below) were not stained (Figure 2A, B). ANT animals showed a trend towards lower numbers of positively stained motoneurons compared to CI animals (646 ± 139 versus 708 ± 95), but this difference was not statistically significant (Figure 2C, p>0.05). DRGs of spinal levels L3-6 showed a similar tendency between ANT and CI animals (Figure 3A, B). ANT animals (851 ± 118) showed less positively traced sensory neurons compared to CI (1038 ± 141), but again, this difference was not statistically significant (Figure 3C, p>0.05). Additionally, preferential regeneration of sensory or motor fibers in ANT or CI animals was neither observed (p>0.05).


Retrograde tracing and toe spreading after experimental autologous nerve transplantation and crush injury of the sciatic nerve: a descriptive methodological study.

van Neerven SG, Bozkurt A, O'Dey DM, Scheffel J, Boecker AH, Stromps JP, Dunda S, Brook GA, Pallua N - J Brachial Plex Peripher Nerve Inj (2012)

Retrograde tracing - α-motor neurons: Images of ANT (A) and CI (B) lumbar spinal cord containing retrograde traced α-motor neurons. Quantification of positively traced neurons revealed no difference in the amount of labelled α-motoneurons between ANT and CI animals (C). Total amount of positively traced motor neurons was counted in lumbar spinal cord segments L3-L6 (D).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3473253&req=5

Figure 2: Retrograde tracing - α-motor neurons: Images of ANT (A) and CI (B) lumbar spinal cord containing retrograde traced α-motor neurons. Quantification of positively traced neurons revealed no difference in the amount of labelled α-motoneurons between ANT and CI animals (C). Total amount of positively traced motor neurons was counted in lumbar spinal cord segments L3-L6 (D).
Mentions: Retrograde tracing with DiI was used to evaluate structural aspects of sciatic nerve regeneration. Representative images and quantification of positively labelled neurons in the spinal cord and DRGs are shown in Figures 2 and 3. Longitudinal sections of the ventral columns revealed positively labelled perikarya in the spinal cord ipsilateral to the lesion site. Logically, α-motor neurons of the contralateral side (below) were not stained (Figure 2A, B). ANT animals showed a trend towards lower numbers of positively stained motoneurons compared to CI animals (646 ± 139 versus 708 ± 95), but this difference was not statistically significant (Figure 2C, p>0.05). DRGs of spinal levels L3-6 showed a similar tendency between ANT and CI animals (Figure 3A, B). ANT animals (851 ± 118) showed less positively traced sensory neurons compared to CI (1038 ± 141), but again, this difference was not statistically significant (Figure 3C, p>0.05). Additionally, preferential regeneration of sensory or motor fibers in ANT or CI animals was neither observed (p>0.05).

Bottom Line: In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading.After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively.No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals.In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Plastic Surgery, Reconstructive and Hand Surgery, Burn Center, Medical Faculty, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany. svanneerven@ukaachen.de.

ABSTRACT
Evaluation of functional and structural recovery after peripheral nerve injury is crucial to determine the therapeutic effect of a nerve repair strategy. In the present study, we examined the relationship between the structural evaluation of regeneration by means of retrograde tracing and the functional analysis of toe spreading. Two standardized rat sciatic nerve injury models were used to address this relationship. As such, animals received either a 2 cm sciatic nerve defect (neurotmesis) followed by autologous nerve transplantation (ANT animals) or a crush injury with spontaneous recovery (axonotmesis; CI animals). Functional recovery of toe spreading was observed over an observation period of 84 days. In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading. After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively. No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals.In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing. The present findings demonstrate that a multimodal approach with a variety of independent evaluation tools is essential to understand and estimate the therapeutic benefit of a nerve repair strategy.

No MeSH data available.


Related in: MedlinePlus