Protection Of The Injured Spinal Cord Nerve Fibers By Progesterone

Spinal cord injury (SCI) causes complete and incomplete function loss from the injury plane of the patient, and brings heavy burden to individual, family and the whole society. After SCI in adult mammal, the formal track of central neural system disappears after a relatively long time. Our research tries to establish a cell culture model and in vivo rat model to prove the protective function of progesterone to degeneration nerve fibers after SCI.Our experiment includes two parts. The first part is to establish a cell culture model, with the hope of using this model to study the protective effects of estrogen and progesterone toward injured axons scaffold at the caudal site. The model was successfully established, but due to the low solubility of progesterone in culture, the direct inhibition of nerve fiber degeneration cannot be detected here.The purpose of the second part is to study the neuroprotection effects of progesterone on the distal part of corticospinal tract (CST) from anterograde degeneration after spinal cord injury. After CST at T8 was complete transected, the PROG group was subcutaneous injected with progesterone dissolved in oil (10mg/ml) every 48h for 2 weeks. The vehicle group received oil only. Ponceau 2R-brilliant green staining method was utilized to stain the tissue sections to show the localization, morphology of CST in spinal cord. The sections showed PROG help the distal nerve fibers of CST more integrated and the array obviously more regular and compact, while the vehicle group contained amounts of severe fragmentations, disorder in array and loss of filaments. The result above suggests PROG can well protect the distal part of corticospinal tract from anterograde degeneration after spinal cord injury.Finally we reach the conclusion that PROG can well protect the distal part of corticospinal tract, and this experiment can serve as a method in studies of axon regeneration, supporting the remaining scaffold to guide the regenerating axons toward a certain direction and ensure a better recover in animal experiments.