Evidence indicating trophic importance of IGF-i in regenerating peripheral nerves
Hansson, H.A.; Dahlin, L.B.; Danielsen, N.; Fryklund, L.; Nachemson, A.K.; Polleryd, P.; Rozell, B.; Skottner, A.; Stemme, S.; Lundborg, G.
Acta Physiologica Scandinavica 126(4): 609-614
1986
ISSN/ISBN: 0001-6772 PMID: 3521205 DOI: 10.1111/j.1748-1716.1986.tb07862.x
Accession: 040080315
The mechanisms influencing regeneration of peripheral nerves are incompletely known, but growth factors are supposed to play a key role. In the present study, we demonstrate, with the aid of immunohistochemical methods, that somatomedin C (Sm-C/insulin-like growth factor I/IGF-I) rapidly increased from low to high concentrations, reaching peak values in 2 weeks, in regenerating sciatic nerves of adult rats. In addition, IGF-I was demonstrated extracellularly, never observed in the control nerves. Reactive Schwann cells appeared to be the major source for IGF-synthesis. Higher concentrations were seen in tubulated nerves as compared to sutured ones. It is proposed that IGF-I exerts important growth supporting effects on regenerating peripheral nerves.
