The present study observed sciatic nerve and gastrocnemius muscle changes in denervated rats using morphology methods, and assessed expression of perlecan, an extracellular matrix com-ponent, which is located at the skeletal muscle cell surface as acetylcholine esterase, as well as synaptophysin, a synaptic marker. Results showed degeneration and inflammation following transection of the sciatic nerve. In addition, the sciatic nerve-dominated skeletal muscle degen-erated with mild inflammation, indicating that skeletal muscle atrophy primarily contributed to denervation-induced nutritional disturbances. With prolonged injury time (1-4 weeks post-injury), perlecan expression gradually decreased and reached the lowest level at 4 weeks, but synap-tophysin expression remained unchanged after denervation. Results suggested that perlecan expression was more sensitive to denervation and reflected regional extracellular matrix changes following denervation.