Neonatal sciatic nerve axotomy causes motoneuron death and muscle denervation atrophy. The aim of the present study was to determine whether insulin-like growth factor-I (IGF-I) administration promotes muscle reinnervation and counteracts motor neuron loss after such an injury. Six weeks after sciatic nerve axotomy performed in 2-day-old pups, the number of motor neurons, as assessed by retrograde transport of horseradish peroxidase injected into the extensor digitorum longus (EDL) muscle, was reduced from 52 +/- 3 to 26 +/- 3. Subsequent administration of IGF-I at the doses of 0.02 mg/kg or 1 mg/kg increased the number of motor neurons to 35 +/- 2 and 37 +/- 5, respectively. The effect on motoneuron survival was accompanied by improved muscle fibre morphometry and restoration of indirect EDL muscle isometric twitch tension, which was about 80 % of control values for both doses of IGF-I compared with 60% observed with saline treatment. Reinnervated EDL muscle from saline-treated rats cannot hold tetanic tension, which is, however, achieved after IGF-I treatment at either dose. Thus, both high and low doses of IGF-I counteracted motoneuron death and improved muscle reinnervation following neonatal sciatic nerve axotomy. IGF-I at 5 microg/kg failed to increase muscle reinnervation.
Systemic administration of insulin-like growth factor decreases motor neuron cell death and promotes muscle reinnervation / L. Vergani, A.M. Di Giulio, M. Losa, G. Rossoni, E. Muller, A. Gorio. - In: JOURNAL OF NEUROSCIENCE RESEARCH. - ISSN 0360-4012. - 54:6(1998), pp. 840-847.
|Titolo:||Systemic administration of insulin-like growth factor decreases motor neuron cell death and promotes muscle reinnervation|
DI GIULIO, ANNA MARIA (Secondo)
MULLER, EUGENIO (Penultimo)
GORIO, ALFREDO (Ultimo)
|Parole Chiave:||muscle reinnervation ; muscle fibre atrophy ; axonal sprouting ; retrograde labelling ; nerve regeneration ; motoneuron survival|
|Settore Scientifico Disciplinare:||Settore BIO/14 - Farmacologia|
|Data di pubblicazione:||1998|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1002/(SICI)1097-4547(19981215)54:6<840::AID-JNR12>3.0.CO;2-L|
|Appare nelle tipologie:||01 - Articolo su periodico|