ABSTRACT
Objectives @#To investigate the effect of sciatic nerve electrical stimulation ( SNES) on motor function recovery in rats with incomplete spinal cord injury (SCI) and its possible mechanism.@*Methods @#The incomplete SCI model was constructed by modified Allen ′s method. Forty⁃five Sprague⁃Dawley (SD) rats were randomly divided into three groups : Sham , SCI , and SNES. Electrical stimulation parameters were 1 ms pulse width and 100 Hz , with 20 mins each time , once a day for 21 days. The motor function was assessed by Basso⁃Beattie⁃Bresnahan (BBB) locomotor function scale , and the action potential conduction was detected by electrophysiology. Hematoxy⁃lin⁃eosin (HE) staining was used to observe the pathological changes in the spinal cord and the average cross⁃sectional area (CSA) of biceps femoris muscle fibers. The number of brain⁃derived neurotrophic factor (BDNF) and tropomyosin⁃related kinase B (TrkB) positive cells , relative mRNA and protein expression were analyzed by immunohistochemistry , reverse transcription polymerase chain reaction (RT PCR) and Western blot separately.@*Results@#On 21 d , the BBB score and average amplitude of action potential of SNES group were higher than those of SCI group , and the difference was statistically significant (P < 0. 05) . Compared with SCI group , the pathological injury of spinal cord tissue in SNES group was significantly improved , and the average CSA of biceps femoris muscles had a statistical difference (P < 0. 05) . The number of BDNF and TrkB positive cells in SNES group was higher than that in SCI group , and there were statistical differences (P < 0. 05) . The relative mRNA and protein expressions of BDNF and TrkB in SNES group were higher than those in SCI group , with statistical differences ( P <0. 05) . The relative mRNA and protein expressions of BDNF and TrkB in SNES group were higher than those in SCI group , with statistical differences ( P <0. 05) . @*Conclusion @#These results show that SNES contributes to alleviating spinal cord tissue injury , promoting the recovery of motor function and delaying the atrophy of muscles below the injury level. The possible mechanism is related to the increased expression of BDNF⁃TrkB proteins.
ABSTRACT
Objective To determine the effect of inhaling rosemary compound essential oil on learning and memory and the expression of choline acetyl transferase (ChAT) in the CA1 region of the hippocampus in rats with vascular dementia (VD).Methods A modified 2-VO method was used to induce permanent brain hypoperfusion,and thus VD,in 60 male SD rats aged 2 months.They were then randomly divided into a normal control group (n =10),a sham-operation group (n =10),a model group (n =10),a rosemary compound essential oil group (n =10) and an edaravone group (n =10).The rosemary compound essential oil group inhaled a compound of the essential oils of rosemary,eugenol and peppermint once a day; the edaravone group was given a daily injection of edaravone injecta.Both the interventions lasted for 65 days.A water maze was used to test their learning and memory abilities.Morphological damage in the CA1 region of the hippocampus and the expression of ChAT were also observed.Results The learning and memory abilities of the model group were significantly weaker compared with the sham-operated group and the normal controls.The rats in the rosemary compound essential oil and edaravone groups were obviously better than those in the model group,but there was no significant difference between rosemary compound essential oil group and the edaravone group.The morphological damage observed in the hippocampus and striatum of the model group was significantly greater,on average,than that observed in the rosemary compound essential oil group and the edaravone group.The average number of ChAT positive units in the CA1 region of the hippocampus was significantly greater in both the rosemary compound essential oil group and the edaravone group compared with the model group,but there was no significant difference between the rosemary compound essential oil group and the edaravone group.Conclusions Inhaling rosemary compound essential oil can improve the learning and memory abilities of rats with VD caused by permanent chronic brain hypoperfusion.It decreases the damage to the neurons of the hippocampus,increases the expression of ChAT,and shows a therapeutic effect on VD,at least in rats.