Preserving Peripheral Nerves In Desiccating Conditions With A Mixture Of Carbon Dioxide And Oxygen Gases

Background:Carbon dioxide acts as a buffer, thereby decreasing the metabolism of the cells in organs and tissues. This study investigated whether peripheral nerve segments in rats could be preserved with mixed carbon dioxide/oxygen gases in desiccating conditions.Methods:In 48 inbred Fischer (F344) 6-week-old male rats, autologous sciatic nerve segments were harvested and preserved in 3 different ways (group B, in mixed carbon dioxide/oxygen gases; group C, in University of Wisconsin solution; and group D, in pure oxygen gas) for 3 weeks at 4℃before being transplanted to bridge sciatic nerve gaps created by the removal of nerve segments in the recipients. Group A nerve segments were transplanted immediately after having been harvested.Results:The viability of the nerve segments was assessed with electron microscopy before transplant, and nerve regeneration was evaluated with electrophysiologic, histologic, and morphologic studies 12 weeks after transplant. The neural cell viability of the preserved nerve segments was confirmed in group B, and demyelination and the disruption of Schwann cells was revealed in groups C and D. The heterotrophic grafted nerves could be regenerated, and target muscles achieved effective reinnervation. As a result, the peripheral nerves were thus integrally preserved in desiccating conditions with a mixture of carbon dioxide/oxygen gases for 3 weeks.Conclusions:Carbon dioxide may therefore have an effective role in isolated tissue preservation.