Selegiline Protects Motoneurons at Acute Phase of Spinal Cord Injury in Hemisectioned rats

Selegiline has neuroprotective and antiapoptotic properties including anti-free radical and neurorophic factors induction. Hemisectioned spinal cord of rat was used to evaluate the effect of selegiline on the acute phase of spinal cord injury. Seven groups were used for studying the dose response, where 2.5 mg/kg (intraperitoneal) was selected as the best dose. Three groups were used for evaluating the neuroprotectivity, one group was sham-operated (SO) while the other two groups were subjected to spinal cord hemisection, which was done at T13 spinal segment level. One group (HT) was treated daily with 2.5 mg/kg selegiline for 21 days while the other was untreated group (HU). All groups were evaluated using Basso Beattie Bresnahan (BBB) behavioral test. Spinal tissues were processed, serially sectioned and stained with Cresyl violet. There were significant differences in the total motoneuron count (TMC) between HT and HU. Two indices were used to evaluate the improvement: the morphometric neuroprotection index and the recovery index (2.72. and 3.8, respectively). The recovery index was calculated using Gompertz model for the data of BBB scores in HT and HU, the maximum BBB scores were 13.75 and 9.33; the times of maximum response were 5.3 and 5.16; and the recovery rate coefficients were 20.6 and 5.32 for HT and HU, respectively. The conclusion is that selegiline is neuroprotective to the acute spinal cord injury.