Zusammenfassung
Fragestellung
Bei Zellschäden im zentralen Nervensystem zeigt die Applikation von Clenbuterol eine
neuroprotektive Wirkung durch die Induktion von Wachstumsfaktoren. Bei Denervation
von Skelettmuskeln führt Clenbuterol außerdem zu einer Minderung der Muskelatrophie.
Dieser Versuch soll zeigen, ob Clenbuterol auch einen Einfluss auf die Regeneration
peripherer Nerven hat.
Methoden und Material
An Versuchsratten wurde der N. ischiadicus vollständig durchtrennt und mikrochirurgisch
koaptiert. Je acht Tiere erhielten über einen Zeitraum von vier bzw. sechs Wochen
Clenbuterol in einer Dosierung von 100 µg/kg/Tag oral appliziert. Kontrollgruppen
erhielten bei gleicher Operation und gleichem Beobachtungszeitraum nur reines Trinkwasser.
Die Auswertung erfolgt histologisch, morphometrisch und klinisch. Das Muskelgewicht
des M. soleus und des M. extensor digitorum wurde als Ratio zur Gegenseite bestimmt.
Ergebnisse
Die histologische und morphologische Untersuchung zeigten eine signifikant höhere
Axonzahl der Clenbuterolgruppen und eine bessere G-Ratio. Das Muskelgewicht war in
der Clenbuterolgruppe nach sechs Wochen signifikant erhöht, und in dieser Gruppe konnten
mehr Tiere die Zehen spreizen.
Schlussfolgerung
Clenbuterol führt im Tierversuch in einer Dosierung von 100 µg/kg/Tag zu einer positiven
Beeinflussung der Regeneration des N. ischiadicus.
Abstract
Purpose
Clenbuterol has shown a neuroprotective action in the central nervous system by induction
of growth factors after cellular damage. Additionally, the atrophy of sceletal muscle
is attenuated by the application of Clenbuterol after denervation. This experiment
was performed to show the influence of Clenbuterol on regeneration of peripheral nerves.
Method and Material
In a rat model, the sciatic nerve was transected and microsurgically coaptated. Eight
animals in each group received a daily oral dosage of 100 µg/kg bodyweight during
four, respectively six weeks. Two control groups received only drinking water under
the otherwise same protocol. The assessment was done histologically, morphometrically
and clinically. The weight ratio of the soleus and extensor digitorum muscles of the
operated to the contralateral side was measured.
Results
The groups treated with Clenbuterol showed histologically and morphometrically a significantly
increased axon count and a better g-ratio. The muscle weight ratio was significantly
higher in the Clenbuterol group after six weeks and more animals in this group were
able to spread their toes.
Conclusion
The oral application of Clenbuterol in a rodent model shows a positive influence on
nerve regeneration.
Schlüsselwörter
Clenbuterol - periphere Nerven - Regeneration - Denervation
Key words
Clenbuterol - peripheral nerves - regeneration - denervation
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Dr. med. Onno Frerichs
Klinik für Plastische, Wiederherstellungs- und Handchirurgie, Otto-von-Guericke-Universität
Magdeburg
Leipziger Straße 44
39120 Magdeburg
Email: Onno.Frerichs@medizin.uni-magdeburg.de