BACKGROUND: It is difficult to repair nerve if proximal stump is unavailable or autogenous nerve grafts are insufficient for reconstructing extensive nerve damage. Therefore, alternative methods have been developed, including lateral anastomosis based on axons' ability to send out collateral sprouts into denervated nerve. The different capacity of a sensory or motor axon to send a sprout is controversial and may be controlled by cytokines and/or neurotrophic factors like ciliary neurotrophic factor (CNTF). The aim of the present study was to quantitatively assess collateral sprouts sent out by intact motor and sensory axons in the end-to-side neurorrhaphy model following intrathecal administration of CNTF in comparison with phosphate buffered saline (vehiculum) and Cerebrolysin. The distal stump of rat transected musculocutaneous nerve (MCN) was attached in an end-to-side fashion with ulnar nerve. CNTF, Cerebrolysin and vehiculum were administered intrathecally for 2 weeks, and all animals were allowed to survive for 2 months from operation. Numbers of spinal motor and dorsal root ganglia neurons were estimated following their retrograde labeling by Fluoro-Ruby and Fluoro-Emerald applied to ulnar and musculocutaneous nerve, respectively. Reinnervation of biceps brachii muscles was assessed by electromyography, behavioral test, and diameter and myelin sheath thickness of regenerated axons. RESULTS: Vehiculum or Cerebrolysin administration resulted in significantly higher numbers of myelinated axons regenerated into the MCN stumps compared with CNTF treatment. By contrast, the mean diameter of the myelinated axons and their myelin sheath thickness in the cases of Cerebrolysin- or CNTF-treated animals were larger than were those for rats treated with vehiculum. CNTF treatment significantly increased the percentage of motoneurons contributing to reinnervation of the MCN stumps (to 17.1%) when compared with vehiculum or Cerebrolysin treatments (at 9.9 or 9.6%, respectively). Reduced numbers of myelinated axons and simultaneously increased numbers of motoneurons contributing to reinnervation of the MCN improved functional reinnervation of the biceps brachii muscle after CNTF treatment. CONCLUSION: The present experimental study confirms end-to-side neurorrhaphy as an alternative method for reconstructing severed peripheral nerves. CNTF promotes motor reinnervation of the MCN stump after its end-to-side neurorrhaphy with ulnar nerve and improves functional recovery of the biceps brachii muscle.

• MeSH
• axony účinky léků   MeSH
• ciliární neurotrofický faktor aplikace a dávkování   MeSH
• krysa rodu Rattus MeSH
• motorické neurony účinky léků   MeSH
• nervový transfer metody   MeSH
• nervus musculocutaneus účinky léků   zranění   patofyziologie   MeSH
• poranění periferního nervu patofyziologie   terapie   MeSH
• potkani Wistar MeSH
• regenerace nervu účinky léků   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ciliární neurotrofický faktor MeSH

Experimental model based on the C5 ventral root avulsion was used to evaluate the efficacy of brain-derived neurotrophic factor (BDNF) and Cerebrolysin treatment on motor neuron maintenance and survival resulted in the functional reinnervation of the nerve stump. In contrast to vehicle, BDNF treatment reduced the loss and atrophy of motor neurons and enhanced the regrowth axon sprouts into the distal stump of musculocutaneous nerve. However, the axon diameter of the myelinated fibers was smaller than those of control rats. The morphometric results were related to a low score in behavioral test similar to vehicle-treated rats. Cerebrolysin treatment greatly protected the motor neurons against cell death. Moreover, morphometric features of myelinated axons were better than those of rats treated with vehicle or BDNF. The mean score of grooming test suggested better results of the functional motor reinnervation than after BDNF administration. The majority of rescued motor neurons regenerating their axons through nerve graft in both BDNF- and Cerebrolysin-treated rats expressed choline acetyltransferase immunostaining. The results demonstrate that BDNF has more modest effects in preventing the death of motor neurons and functional recovery of injured motor nerve after root avulsion than Cerebrolysin.

• MeSH
• aminokyseliny aplikace a dávkování   farmakologie   MeSH
• axony fyziologie   MeSH
• cholin-O-acetyltransferasa metabolismus   MeSH
• chování zvířat účinky léků   MeSH
• dextrany MeSH
• fluorescenční barviva MeSH
• imunohistochemie MeSH
• kosterní svaly inervace   MeSH
• krysa rodu Rattus MeSH
• kůže inervace   MeSH
• mícha fyziologie   MeSH
• míšní kořeny fyziologie   MeSH
• míšní nervy fyziologie   transplantace   MeSH
• motorické neurony účinky léků   fyziologie   MeSH
• mozkový neurotrofický faktor aplikace a dávkování   farmakologie   MeSH
• nervová vlákna myelinizovaná fyziologie   MeSH
• nervus musculocutaneus cytologie   fyziologie   MeSH
• neuroprotektivní látky aplikace a dávkování   farmakologie   MeSH
• potkani Wistar MeSH
• regenerace nervu fyziologie   MeSH
• rhodaminy MeSH
• spinální injekce MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• aminokyseliny MeSH
• cerebrolysin MeSH Prohlížeč
• cholin-O-acetyltransferasa MeSH
• dextrany MeSH
• fluorescenční barviva MeSH
• Fluoro-Ruby MeSH Prohlížeč
• mozkový neurotrofický faktor MeSH
• neuroprotektivní látky MeSH
• rhodaminy MeSH