Cyclosporine-A delays the end-plate degeneration in denerved rat muscles

When an adult skeletal muscle is denervated, its end‐plates degenerate and their acethylcholinesterase (AChE) activity gradually decreases. However, if the proximal segment of the nerve is sutured to the distal segment, or if the nerve is implanted in a previous denerved muscle the axons regenerate and reconstitute new end‐plates over a variable period. This period depends on the time passed between the nerve cutting and the reimplantation suggesting that the degenerative processes are closely correlated to regeneration. It has been shown that cyclosporine‐A (CsA) is useful in nerve regeneration but their role in nerve degeneration is not well understand. We evaluated, using AChE histochemistry, the effects of CsA, on the degeneration of the end‐plates in an experimental model of gastrocnemius muscle denervation in the rat. CsA at a dose of 15 mg/kg/day did not cause any quantitative or qualitative alterations in the end‐plates on normal rat muscles. Moreover, our findings showed that CsA reduced the end‐plate degeneration and loss in the denerved rat muscles.