| Objective: To establish a simple, stable and low death rate tSCI model of rat and explore the effect of EGB and PNS on the expression of NGF and BDNF in spinal cord following transected injury. Furthermore, the molecular mechanism both EGB and PNS for SCI recovery was investigated.Methods: 95 adult female SD rats, ranging from 200g to 220g, were used. 45 of them were divided at random into two groups-transected spinal cord injury group (30), in which the spinal cord was transected at T12 completely, and sham operation group(15), in which the dura mater of spinal cord was cut but the spinal cord remained intact. The normative nursing project was employed to rats so as to preclude the complication and reduce the death rate of rats following tSCI. BBB score, SEP (somatosensory evoked potential) and HE staining technique were adopted to assess the animals, surviving for 24h, 1w, 1m after operation respectively. The BBB scores and SEP were recorded and analyzed by two-samples T test. 50 of them were divided at random into five groups: SO control group (10), tSCI control group (10), NS (saline) control group(lO), EGB therapy group (10)and PNS therapy group (10). The animals were put to death at 24h or Iw after operation and 5 rats were used in each point. The spinal cord of each rat was taken out at L2 and then was put into 4% polymerisatum for 12h, and then into 20% sucrose PBS over night. Then, the spinal cord was made into 20nm frozen sections, stained with HE and under the same condition using specific NGF and BDNF antibody by the immunohistochemistry ABC method. Data of the number of survival motor neurons, positive neurons both NGF and BDNF in the ventral horn of spinal cord were analyzed by one-way ANOVA and q test.Results: BBB scores of the locomotor function of the hindlimbs were 21?.00 in the two groups before operation, but they were only 4.37?.36 at 1m after transected spinal cord injury in tSCI group(P<0.01). There had no apparent decrease of BBB scores in SO group (15.77?.37, 18.03?.46, 21.0?.00 at 24h, 3d and after 7d respectively) compared with those of normal adult rats(P>0.05). The scores were significant difference between SO group and tSCI group at 24h, 3d, 7d, 14d, 21d, 30d(P<0.01). At 1m after operation, the latent period of PI and Nl wave of SEP were normal in S group, whereas those of tSCI group had no sign of wave being recorded. The differences were significant(P<0.01). The incidence of hematuresis, uroschesis, abdominal distention, hydroperitonia and self-mutilation as well as lateral curvature of spine was 20%, 100%, 100%, 100%, 10%, 80%, respectively. The death rate was 20% in tSCI group. All survival rats didn't recover incompletely independent defecation activities until 9~15days after tSCI. Pathologic changes of spinal cord were apparent after tSCI. But these changes above-mentioned were slighter in EGB and PNS therapy group than those of tSCI and NS group. The number of neurons in the ventral horn of spinal cord in tSCI group had no apparent change compared with that of NS group at 24h and 7d (P>0.05), and there had also no change between EGB and PNS therapy group (P>0.05), but that of EGB and PNS therapy group increased significantly than that of tSCI control group and NS control group. There was also apparent difference about the number of neurons in SO group compared with that of the above four groups at any time (P<0.05). The increasing expression of NGF and BDNF4positive cells was observed at 24h after operation in EGB and PNS group, but it was observed until 7d after operation in tSCI control group and NS control group. The number of NGF, BDNF positive cells in the ventral hom of spinal cord in tSCI group had no apparent change compared with that of NS group at 24h and 7d (P>0.05), and there had also no change between EGB and PNS therapy group (P>0.05), but that of EGB and PNS therapy group increased significantly than that of tSCI control group and NS control group. There had also apparent difference about the number of NGF and BDNF positive cells in SO group compa...
|
PDF Full Text Request