Investigation of the dose-dependency of citicoline effects on nerve regeneration and functional recovery in a rat model of sciatic nerve injury.

AIM The aim of this study was to investigate the dose dependence of citicoline's previously-reported effects on recovery of peripheral nerve injury. MATERIAL AND METHODS Right sciatic nerves of sixty adult female Wistar Albino rats were incised and primary anastomosis was performed. Rats were then divided into four groups: Control group received 2 ml of saline intraperitoneally, while rats in C-300, C-600 and C-900 groups received 300 μmol/kg, 600 μmol/kg and 900 μmol/kg citicoline dissolved in 2 ml saline, respectively. Rats were tested for sciatic functional index (SFI) on the 4th, 8th and 12th weeks and electrophysiological recordings were obtained on the 12th week. Rats were then sacrificed to investigate nerve adhesions and perform histomorphological examinations. RESULTS Our results showed that rats in C-600 and C-900 groups had significantly lesser neural adhesion and greater SFI and electrophysiological score than those in the Control and C-300 groups (p < 0.05). Mean density and total number of functionally myelinated axons were significantly increased in C-900 group, while perineural scar tissue formation was reduced in all citicoline-treated groups. CONCLUSION We conclude that citicoline exhibits dose-dependent effects on axonal regeneration and recovery without scar formation in a rat model of peripheral nerve incision and primary anastomosis.