RESUMO
Apoptosis is a gene-based programmed death of cells during physiological conditions such as development and aging. Also, apoptotic pathways can be activated in different kinds of tissues under different pathological background such as hormonal changes, toxic agents, or ischemia / reperfusion injury. In this study we tested the effect of ischemia / reperfusion injury for a brief period on terminal Schwann cells of peripheral motor nerve endings. We hypothesize that terminal Schwann cells are sensitive and undergo apoptotic changes under ischemic insult. Therefore, we subjected 8 Wistar rat left legs to 30 min ischemia followed by 15 min reperfusion. The right legs were used as controls. Extensor digitorum longus muscles were dissected and processed for transmission electron microscopic study. Results demonstrated apoptotic changes in terminal Schwann cells and disappearance of basal lamina of neuromuscular junctions. In contrast, muscle fibers did not show any concurrent pathological changes. This indicates that apoptotic changes in Schwann cells would trigger delayed pathological response in muscle fibers. Therefore, more attention would be paid to motor axon terminals as a starting point for pathogenesis and perhaps therapy of motoneuron and neuromuscular diseases