Neurotrophin-4 delivered by fibrin glue promotes peripheral nerve regeneration

Neurotrophin-4 (NT-4) is a recently identified neurotrophic factor with pot ential trophic effects on subpopulations of neurons. Little is known about its role in peripheral nerve regeneration following nerve injury. To invest igate this, 48 Sprague-Dawley rats underwent left sciatic nerve transection and immediate repair. Fibrin glue mixed with either NT-4 or vehicle (contr ol) was injected around the nerve repair site. Nerve regeneration was asses sed both functionally and histomorphometrically. The results showed that th e NT-4-treated group had a significant increase compared with the control i n the regeneration distance at 5 days. The sciatic function index was signi ficantly greater in the NT-4 group from 40 to 60 days after nerve repair. M orphometric analysis revealed that nerves treated with NT-4 had significant improvement in the number of regenerated axons, axonal diameter, and myeli n thickness. These results suggest that NT-4 is a potent factor improving r at sciatic nerve regeneration. (C) 2001 John Wiley & Sons, Inc.