ABSTRACT
Objective To study the morphological changes of the Schwann cells within the predegenerated nerve. Methods The ulanr and the median nerves were cut bilaterally at the axillary level in 42 SD rats. A nerve segment of 1 cm in length was harvested from the distal segment of each of the cut nerves right after the operation, 3 days, 1, 2, 3, 4 and 8 weeks postoperatively(group 1-7). The methods of Schwann cells culture and S-100 protein standing were used to study the temporal changes of the number of the Schwann cells, and the thickness of myelin of the predegenerated nerve were studied under electromicroscope. Results The number of Schwann cells increased after nerve transection, and reached a peak of [(3.52?0.27)?107]/ml in one week. The thickness of myelin also increased after nerve transection, and was thickest at about (231.2?8.9) nm in one week. The myelin thickness slowly decreased after this time. Conclusion The number of the Schwann cells and the thickness of myelin of the predegenerated nerve were changed with time.