Objective The potential of all central nervous system synapses to exhibit long term potentiation （LTP） or long term depression （LTD） is subject to modulation by prior synaptic activity, a higher-order form of plas...Objective The potential of all central nervous system synapses to exhibit long term potentiation （LTP） or long term depression （LTD） is subject to modulation by prior synaptic activity, a higher-order form of plasticity that has been termed metaplasticity. This study is designed to examine the plasticity and metaplasticity in the lateral perforant path of rat. Methods Field potential was measured with different priming and conditioning stimulation protocols. Results Ten-hertz priming, which does not affect basal synaptic transmission, caused a dramatic reduction in subsequent LTP at lateral perforant path synapses in vitro, and the reduced LTP lasted for at least 2 h. The LTD was unaffected. The reduction of LTP in the lateral perforant path was also readily induced by applying priming antidromically at the mossy fibers. Conclusion Priming with 10 Hz, which is within a frequency range observed during physiological activity, can cause potent, long-lasting inhibition of LTP, but not LTD. This form of metaplasticity adds a layer of complexity to the activity-dependent modification of synapses within the dentate gyrus.展开更多
The frequency range of electroacupuncture in treatment of Alzheimer＇s disease in rats is commonly 2-5 Hz（low frequency） and 50-100 Hz（high frequency）. We established a rat model of Alzheimer＇s disease by injecti...The frequency range of electroacupuncture in treatment of Alzheimer＇s disease in rats is commonly 2-5 Hz（low frequency） and 50-100 Hz（high frequency）. We established a rat model of Alzheimer＇s disease by injecting β-amyloid 1-42（Aβ1-42） into the bilateral hippocampal dentate gyrus to verify which frequency may be better suited in treatment. Electroacupuncture at 2 Hz or 50 Hz was used to stimulate Baihui（DU20） and Shenshu（BL23） acupoints. The water maze test and electrophysiological studies demonstrated that spatial memory ability was apparently improved, and the ranges of long-term potentiation and long-term depression were increased in Alzheimer＇s disease rats after electroacupuncture treatment. Moreover, the effects of electroacupuncture at 50 Hz were better than that at 2 Hz. These findings suggest that high-frequency electroacupuncture may enhance hippocampal synaptic transmission and potentially improve memory disorders in Alzheimer＇s disease rats.展开更多
钙/钙调蛋白依赖性蛋白激酶Ⅱ(calcium/calmodulin-dependent protein kinaseⅡ,CaMKⅡ)是一种重要的丝氨酸/苏氨酸蛋白激酶,参与脑内多种神经活动的调节,并被认为是一个"记忆分子",在突触可塑性和学习记忆中发挥关键作用。C...钙/钙调蛋白依赖性蛋白激酶Ⅱ(calcium/calmodulin-dependent protein kinaseⅡ,CaMKⅡ)是一种重要的丝氨酸/苏氨酸蛋白激酶,参与脑内多种神经活动的调节,并被认为是一个"记忆分子",在突触可塑性和学习记忆中发挥关键作用。CaMKⅡ的功能正常对于大脑的正常生理活动是必需的。近年来研究发现,许多神经精神疾病的发生都与脑内CaMKⅡ的功能异常有关。该文对CaMKⅡ在突触可塑性以及神经精神疾病中的作用做一综述。展开更多
文摘Objective The potential of all central nervous system synapses to exhibit long term potentiation （LTP） or long term depression （LTD） is subject to modulation by prior synaptic activity, a higher-order form of plasticity that has been termed metaplasticity. This study is designed to examine the plasticity and metaplasticity in the lateral perforant path of rat. Methods Field potential was measured with different priming and conditioning stimulation protocols. Results Ten-hertz priming, which does not affect basal synaptic transmission, caused a dramatic reduction in subsequent LTP at lateral perforant path synapses in vitro, and the reduced LTP lasted for at least 2 h. The LTD was unaffected. The reduction of LTP in the lateral perforant path was also readily induced by applying priming antidromically at the mossy fibers. Conclusion Priming with 10 Hz, which is within a frequency range observed during physiological activity, can cause potent, long-lasting inhibition of LTP, but not LTD. This form of metaplasticity adds a layer of complexity to the activity-dependent modification of synapses within the dentate gyrus.
基金supported by the National Natural Science Foundation of China,No.81373741
文摘The frequency range of electroacupuncture in treatment of Alzheimer＇s disease in rats is commonly 2-5 Hz（low frequency） and 50-100 Hz（high frequency）. We established a rat model of Alzheimer＇s disease by injecting β-amyloid 1-42（Aβ1-42） into the bilateral hippocampal dentate gyrus to verify which frequency may be better suited in treatment. Electroacupuncture at 2 Hz or 50 Hz was used to stimulate Baihui（DU20） and Shenshu（BL23） acupoints. The water maze test and electrophysiological studies demonstrated that spatial memory ability was apparently improved, and the ranges of long-term potentiation and long-term depression were increased in Alzheimer＇s disease rats after electroacupuncture treatment. Moreover, the effects of electroacupuncture at 50 Hz were better than that at 2 Hz. These findings suggest that high-frequency electroacupuncture may enhance hippocampal synaptic transmission and potentially improve memory disorders in Alzheimer＇s disease rats.
文摘钙/钙调蛋白依赖性蛋白激酶Ⅱ(calcium/calmodulin-dependent protein kinaseⅡ,CaMKⅡ)是一种重要的丝氨酸/苏氨酸蛋白激酶,参与脑内多种神经活动的调节,并被认为是一个"记忆分子",在突触可塑性和学习记忆中发挥关键作用。CaMKⅡ的功能正常对于大脑的正常生理活动是必需的。近年来研究发现,许多神经精神疾病的发生都与脑内CaMKⅡ的功能异常有关。该文对CaMKⅡ在突触可塑性以及神经精神疾病中的作用做一综述。
基金supported by the National Natural Science Foundation of China(No.61074131)the Postgraduate Innovation Fund of Tianjin Medical UniversityChina(No.2010GSI09)
