Effects of L-carnitine, L-acetylcarnitine and gangliosides on the regeneration of the transected sciatic nerve in rats

Three pharmacological agents, L-carnitine, L-acetylcarnitine and gangliosides, were tested for their ability to enhance the regeneration of the rat sciatic nerve following transection and microsurgical repair. The drugs were administered intraperitoneally at the dose of 50 mg/kg/d for 28 and 56 d postoperatively. At the end of treatment, the motor function recovery of the peroneal component of the sciatic nerve was assessed and the regenerated nerves were analysed morphometrically on histological semi-thin sections. Also, the reinnervated extensor digitorum longus (EDL) muscles were studied histochemically using the adenosine-triphosphatase (ATP-ase) technique 56 d after surgery. Motor function assessment at 56 d after nerve repair revealed that L-acetylcarnitine-treated animals recovered a clinical grade significantly higher (p less than 0.05) than the control animals. Twenty-eight days after nerve repair, the number of myelinated fibres was significantly higher (p less than 0.05) in L-acetylcarnitine and ganglioside-treated animals than in control animals. However, 56 d after nerve repair the number of regenerated fibres in all the drug-treated groups was not significantly different from that of the control group. The EDL muscles of the drug-treated animals did not show significant differences from those of control animals with respect to fibre composition and fibre diameter although the L-acetylcarnitine-treated animals exhibited a significantly lower (p less than 0.05) degree of muscle atrophy than did the control animals. The results of the present work seem to indicate that L-acetylcarnitine and to a lesser extent gangliosides exert some favourable effect on the regeneration of the transected sciatic nerve in rats.(ABSTRACT TRUNCATED AT 250 WORDS)