Regeneration along intact nerves using nerve growth factor and ciliary neurotrophic factor

The purpose of this investigation was to evaluate the ability of a specific growth factor combination, nerve growth factor (NGF) and ciliary neurotrophic factor (CNTF), to enhance peripheral nerve regeneration. Eight groups of eight Sprague-Dawley rats underwent repair of a nerve gap defect: Group A (immediate repair), Group B (intact nerve bridge), Group C (nerve autograft), Group D (gap in situ), Group E (NGF + CNTF), Group F (NGF), Group G (CNTF), and Group H (saline). Twelve weeks after surgery, analysis included the measurement of the isometric force of muscle contraction for the tibialis anterior muscle and tissue harvesting for both quantitative and qualitative analysis. When evaluating muscle contraction force, there was no statistically significant difference among the experimental groups receiving a growth factor injection and the normal saline control group. The hypothesis of this study was that peripheral nerve regeneration could be enhanced by the combination of NGF and CNTF. The evidence does not support this hypothesis.