Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add filters








Language
Year range
1.
Article in Chinese | WPRIM | ID: wpr-479993

ABSTRACT

Objective To investigate the effects of functional electrical stimulation (FES) on motor function and on the expression, proliferation, migration and differentiation of endogenous neural stem cells in the subventricular zone (SVZ) after cerebral ischemia.Methods Middle cerebral artery occlusion (MCAO) was used to induce a model of cerebral ischemia in 108 rats using the modified Zea-Longa method of intraluminal filament occlusion.They were then randomly divided into an FES group, a placebo stimulation group and a control group with 36 cases in each.Superficial FES electrodes were pasted on the paralyzed forelimbs of the rats in the first two groups, though FES treatment was administered only to the FES group beginning on the 3rd day after the MCAO operation.The stimulation was designed to produce extension of the wrist and digits of the paralyzed forelimb.Before, and after 1,3, 7 and 14 days of the treatment, the neurological deficit was evaluated using modified neurological severity scoring (mNSS).BrdU +/GFAP+, BrdU+/DCX+ and BrdU+/NeuN + cells in the SVZ were detected using immunofluorescence technique.Results After 7 and 14 days of treatment, the average motor function of the rats in the FES group had improved significantly when compared with the averages of the other two groups.Compared with the other two groups, the average number of BrdU +/GFAP+ positive cells in the ischemic SVZ was also significantly greater in the FES group after 7 and 14 days of treatment.After 14 days, BrdU +/Dcx + positive cells in the FES group had also increased significantly more,but only a few BrdU +/NeuN + cells had appeared in any of the three groups.Conclusion FES can improve motor function after cerebral ischemia, and promote proliferation and differentiation of neural stem cells in the SVZ.

2.
Article in Chinese | WPRIM | ID: wpr-479992

ABSTRACT

Objective To study the effects of different types of exercise training on learning and memory, as well as on the expression of synaptophysin (SYP) and on postsynaptic density protein 95 (PSD-95) in rats in which a model of vascular dementia had been created.Methods Forty male Wistar rats were divided randomly into a voluntary exercise group (V-EX) , a forced exercise group (F-EX) , an involuntary exercise group (I-EX) , a vascular dementia group (VD) and a sham-operation group (Sham) , with 8 rats in each group.Two-vessel occlusion (2-VO) of the arteria carotis communis was used to create a model of vascular dementia in all of the rats except those in the sham-operation group.Beginning one week after the surgery, the V-Ex rats were free to run in a running wheel.The F-EX rats were forced to run 270 m a day in an electric wheel.The I-EX rats were stimulated to imitate the gait pattern of their forelimbs running at 9 m/min three times a day for l0 minutes each time.No special training was given to the rats in the other 2 groups.Three weeks after the surgery, their learning and memory were tested using a novel object recognition test.Immediately after the test, their prefrontal cortex was sampled and the expression of SYP and PSD-95 was detected using western blotting.Results The average novel object recognition indices of the rats in the V-EX, F-EX and I-EX groups were all significantly higher than that of the VD group.Average PSD-95 expression was also significandy higher than in the VD group.Conclusion Exercise, whether voluntary, forced or induced by functional electrical stimulation can improve learning and memory in vascular dementia, at least in rats.The mechanism is possibly that the training can increase the expression of PSD-95 in the prefrontal cortex, though not SYP.

3.
Article in Chinese | WPRIM | ID: wpr-430475

ABSTRACT

Objective To investigate the effects of repeated high frequency transcranial magnetic stimulation (rTMS) on spatial learning and memory function,and on long-term potentiation (LTP) after global cerebral ischemia and reperfusion,and to explore the mechanisms involved.Methods Eighty-three male Wistar rats were studied.Five were tested to determine their average motor threshold (Tm).The others were divided into a normal control group,a cerebral ischemia and reperfusion model group and an rTMS group.Cerebral ischemia was induced with the four vessel occlusion method for 10 minutes.The rTMS treatment protocol (10 Hz stimulation for 5 s at the resting threshold,twice a day) was applied over a 2-week period from day 3 post-operation.The Morris water maze test was performed to observe spatial learning and memory at post-operation day 2 and day 4.The field excitatory postsynaptic potentials,population spike and the magnitude of long-term potentiation (LTP) induced by theta burst electric stimulation were recorded from the perforant path to the dentate gyrus (PP-DG).Results At post-operation day 3,rats in the untreated cerebral ischemia and reperfusion model group exhibited a significant decrease in the magnitude of the PP-DG LTP as compared to the normal group.No significant difference in LTP was found between the model group and the rTMS group.After the 2 weeks of treatment the LTP levels in the rTMS treated group were significantly higher than in the two untreated groups.In the Morris water maze testing,the average escape latency in the rTMS group was significantly shorter than that of the cerebral ischemia and reperfusion model group (which was not treated).In the probe trials,the time in the original quadrant of the platform and the time of crossing the platform were both significantly less for the rTMS-treated rats than for those not treated.Conclusions High frequency rTMS can improve spatial learning and memory after global cerebral ischemia and reperfusion by enhancing the LTP induced in the hippocampus.High frequency rTMS might exert this beneficial effect by modulating the function of intermediate neurons in the hippocampal neuronal network and by promoting neurotransmitter release.

4.
Article in Chinese | WPRIM | ID: wpr-419734

ABSTRACT

Objective To investigate the effects of functional electrical stimulation (FES) on motor function and the expression of bromodeoxyuridine (Brdu) + and glial fibrillary acid protein (GFAP) + in the subventricular zone (SVZ) of rats with acute cerebral infarction,and to explore it's mechanism. Methods A rat model of cerebral infarction was established using Longa's technique for middle cerebral artery occlusion (MCAO) with an intraluminal filament.The rats were randomly divided into a FES group,a placebo stimulation group and a control group.In each group,rats were randomly allocated into 1 d,3 d,7 d and 14 d subgroups (6 rats/subgroup).Superficial electrodes were pasted on the paralyzed forelimbs of rats in the FES group for connecting with the FES instrument,and FES treatment was carried out with a current of 4-5 mA for 15 min on the third day after the MCAO operation to produce extension of the wrist and the digits of the paralyzed forelimb.The rats in the placebo stimulation group were pasted with electrodes,but no FES was administered and they received no other treatment.Neurological deficits were evaluated using the modified neurological severity score (mNSS) before treatment and on the 1 st,3rd,7th,and 14th day after treatment. BrdU and GFAP positive cells in the SVZ were detected by immunofluorescence techniques.Results After 7 or 14 days the motor function of rats in the FES group had improved significantly compared with the placebo stimulation and control groups.Compared with the other two groups,the expression levels of BrdU+ and GFAP+ cells in the ischemic SVZ in the FES group were significantly higher at the 3rd,7th and 14th day.Conclusion FES can improve motor function after acute cerebral infarction and also promote the proliferation and differentiation of neural stem cells in the SVZ.

SELECTION OF CITATIONS
SEARCH DETAIL