Objective:To investigate the effect of neurotrophin-3 on the expressions of SOD and MDA in the injured spinal cord of rats. Methods: Totally 105 SD rats were randomly divided into 3 groups (n = 35): sham group, contro...Objective:To investigate the effect of neurotrophin-3 on the expressions of SOD and MDA in the injured spinal cord of rats. Methods: Totally 105 SD rats were randomly divided into 3 groups (n = 35): sham group, control group and experimental group. Animal model of acute spinal cord was inflicted with Allen's method by a thin plastic tube situated in subarachnoid space below the injury level for perfusion. Rats in experimental group received 20μl NT-3 (200 ng) from the tube at 0, 4. 8. 12. 24 h and 3. 7 d after injury, and those in control group got the equal volume of normal saline at the same time points. The animals in sham group only received opening vertebral plate and putting tube in subarachnoid space. The rats were sacrificed at 4, 8. 12. 24 h, and 3. 7, 14 d postinjury (n = 5). And the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in blood were observed with colorimetric method. Results: The serum level of SOD reduced obviously and the level of MDA raised obviously in rats after the injury, and the activity of SOD reached the lowest on day 3 and the concentration of MDA reached peak at the 7 d. In the experimental group, the SOD level was obviously higher (P<0. 01). and MDA level was lower than the control (P<0. 01). Conclusion:NT-3 can mitigate secondary injury of spinal cord in vivo. One of mechanisms is that inhibits abnormal expression of MDA and elevates the activity of SOD. thus the injury of free radical and lipid peroxidation is attenuated.展开更多
Objective： To study the protective mechanisms of neurotrophin-3 （NT-3） on the spinal cord injury. Methods：Totally 105 SD rats were randomly divided into 3 groups： control group, experimental group and sham operat...Objective： To study the protective mechanisms of neurotrophin-3 （NT-3） on the spinal cord injury. Methods：Totally 105 SD rats were randomly divided into 3 groups： control group, experimental group and sham operation group. Rats from the former 2 groups were inflicted to animal model of acute spinal cord injury according to Allen＇s （WD） by situating a thin plastic tube in the subarachnoid space below the injury level for perfusion. Rats in experimental group received 20 ul NT-3 （200 ng） from the tube at 0, 4, 8, 12, 24 h and 3, 7 d after injury, and those in control group got an equal volume of normal saline at the same time. The animals in sham operation group only received opening vertebral plate and tube was put in subarachnoid space. The rats were sacrificed at 4, 8, 12, 24 h and 3, 7, 14 d post injury （n=5）. The expression levels of Bcl-2 and Bax proteins in spinal cord of rats were detected by immunohistochemistry assay. Results： The level of Bax protein in control group significantly increased as compared with those in sham operation group, and the peak reached at 8 h after spinal cord injury. The Bcl-2 proteins were always weakly positive. The Bax proteins in NT-3 group significantly decreased but the Bcl-2 proteins obviously increased as compared with those in control group. Conclusion： NT-3 can protect spinal cord from injury in vivo. One of the mechanisms is that NT-3 can inhibit abnormal expression of Pax protein, and increase the expression of Bcl-2 protein, then inhibit apoptosis after spinal cord injury.展开更多
文摘Objective:To investigate the effect of neurotrophin-3 on the expressions of SOD and MDA in the injured spinal cord of rats. Methods: Totally 105 SD rats were randomly divided into 3 groups (n = 35): sham group, control group and experimental group. Animal model of acute spinal cord was inflicted with Allen's method by a thin plastic tube situated in subarachnoid space below the injury level for perfusion. Rats in experimental group received 20μl NT-3 (200 ng) from the tube at 0, 4. 8. 12. 24 h and 3. 7 d after injury, and those in control group got the equal volume of normal saline at the same time points. The animals in sham group only received opening vertebral plate and putting tube in subarachnoid space. The rats were sacrificed at 4, 8. 12. 24 h, and 3. 7, 14 d postinjury (n = 5). And the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in blood were observed with colorimetric method. Results: The serum level of SOD reduced obviously and the level of MDA raised obviously in rats after the injury, and the activity of SOD reached the lowest on day 3 and the concentration of MDA reached peak at the 7 d. In the experimental group, the SOD level was obviously higher (P<0. 01). and MDA level was lower than the control (P<0. 01). Conclusion:NT-3 can mitigate secondary injury of spinal cord in vivo. One of mechanisms is that inhibits abnormal expression of MDA and elevates the activity of SOD. thus the injury of free radical and lipid peroxidation is attenuated.
文摘Objective： To study the protective mechanisms of neurotrophin-3 （NT-3） on the spinal cord injury. Methods：Totally 105 SD rats were randomly divided into 3 groups： control group, experimental group and sham operation group. Rats from the former 2 groups were inflicted to animal model of acute spinal cord injury according to Allen＇s （WD） by situating a thin plastic tube in the subarachnoid space below the injury level for perfusion. Rats in experimental group received 20 ul NT-3 （200 ng） from the tube at 0, 4, 8, 12, 24 h and 3, 7 d after injury, and those in control group got an equal volume of normal saline at the same time. The animals in sham operation group only received opening vertebral plate and tube was put in subarachnoid space. The rats were sacrificed at 4, 8, 12, 24 h and 3, 7, 14 d post injury （n=5）. The expression levels of Bcl-2 and Bax proteins in spinal cord of rats were detected by immunohistochemistry assay. Results： The level of Bax protein in control group significantly increased as compared with those in sham operation group, and the peak reached at 8 h after spinal cord injury. The Bcl-2 proteins were always weakly positive. The Bax proteins in NT-3 group significantly decreased but the Bcl-2 proteins obviously increased as compared with those in control group. Conclusion： NT-3 can protect spinal cord from injury in vivo. One of the mechanisms is that NT-3 can inhibit abnormal expression of Pax protein, and increase the expression of Bcl-2 protein, then inhibit apoptosis after spinal cord injury.
