Exploring the mechanism of different frequencies of rTMS in improving learning and memory abilities in middle cerebral artery occlusion rats based on Notch1 pathway
10.3969/j.issn.1001-1242.2024.08.002
- VernacularTitle:基于Notch1通路探讨不同频率重复经颅磁刺激改善大脑中动脉闭塞大鼠学习记忆能力的机制
- Author:
Yansheng YE
1
;
Lai LUO
;
Deshun XU
Author Information
1. 福建医科大学附属南平市第一医院中医康复科,福建省南平市,353000
- Publication Type:Journal Article
- Keywords:
low-frequency/high-frequency transcranial magnetic stimulation;
post-stroke cognitive impairment;
middle cerebral artery occlusion;
learning and memory;
Notch1 pathway
- From:
Chinese Journal of Rehabilitation Medicine
2024;39(8):1084-1093
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To observe the effects of repetitive transcranial magnetic stimulation (rTMS) at different frequencies on learning and memory abilities in rats during the early recovery phase of middle cerebral artery occlusion (MCAO) and to explore the underlying mechanisms.Method:Successfully modelled MCAO rats were randomly divided into the model group,low-frequency group,high-frequency group,and sham-operated group was set up at the same time,with 12 rats in each group. The low-frequency group and high-frequency group were stimulated with a CCY-I transcranial magnetic stimulator 2 times/day for 14d;the low-frequency group was treated with 1Hz at the left prefrontal lobe of the rat's skull,and the high-frequency group was treated with 10Hz at the right prefrontal lobe. The model group and the sham-operated group were not treated but were subjected to the same conditions of handling and re-straint before returning to their cages. Neurobehavioral scores were recorded on the 1st and 14th day after the operation;the Morris water maze test was conducted on day 3—7 after the operation;TTC staining,PCR and Western blot to detect the mRNA and protein expression of key genes (Notch1,Hes1,Hes5) were performed at the end of the intervention on the 14th postoperative day. Result:①Neurological deficit scores:After 14 days of intervention,both the high-frequency and low-frequency groups showed a reduction in neurofunctional compared to the model group (P<0.05),with no significant dif-ference between the model group and high-frequency group (P>0.05). ②Morris water maze experiment:The av-erage escape latency during the directional navigation experiment was significantly reduced day by day in the low frequency group,high frequency group and sham operation group (P<0.05). The escape latency was short-er in the high-frequency group compared to the model group,and shorter in the low-frequency group com-pared to the high-frequency group (P<0.05). The number of platform crossings in the spatial exploration experi-ment showed no significant difference between low frequency group and sham operation group,high frequency group and model group (P>0.05). The high-frequency group and the model group had fewer crossing than the sham operation group,and the low-frequency group had more than the model group and high-frequency group (P<0.05). ③TTC staining:The infarct size in the low-frequency group and high-frequency group was signifi-cantly smaller than in the model group. ④PCR and Western blot:Compared to the model group,the high fre-quency group and the low frequency group had significantly increased mRNA and protein expression of Notch1,Hes1 and Hes5 (P<0.05). There was no significant difference in the mRNA and protein expression of Notch1,Hes1 and Hes5 between the low frequency group and high frequency group (P>0.05).Conclusion:Both high and low frequency rTMS can improve the learning and memory abilities in MCAO rats,potentially by activating and increasing the expression of the Notch1 pathway in hippocampal tissues,which improves the synaptic plasticity of hippocampus.
