GABA紧张性抑制电流及其对癫痫的功能性研究

GABA Tonic Inhibition and its Functional Study of Epilepsy

GABA是神经系统中主要的抑制性递质之一。GABA在突触的轴突末端经谷氨酸脱羧合成而成,经囊泡运输至突触前膜,突触前膜释放GABA,作用于突触后膜的GABA受体,引起抑制性效应。依据GABA存在的位置和传递方式的不同,GABA介导的电流特性也不相同。GABA存在于突触内,在突触之间传递,介导的是Phaisc inhibition(相位性抑制)电流。若GABA存在于突触外,如突触间隙,细胞间隙,通过传递作用于突触后膜,介导的则是Tonic inhibition(紧张性抑制)电流。由于GABA存在的位置和传递方式有所不同,因此相位性抑制电流和紧张性抑制电流有各自的特点。相位性电流是间歇性的。而GABA紧张性抑制电流具有持续性的特点。同时,GABA紧张性抑制电流还具有高亲和力和低脱敏性的特点,这使得GABA紧张性抑制电流在影响细胞电位时具有比其他抑制性电流更显著和快速的作用,因此对疾病发生也具有重要意义的机制。研究GABA紧张性抑制电流对了解神经网络的活动有重要意义,同时也能深入了解疾病发生的机制,并作为预防或治疗疾病发生的有力靶点。

GABA is one of the major inhibitory neurotransmitter in the nervous system. GABA in the axon terminal synapses by glutamate synthesis and decarboxylation, the vesicle transport to the presynaptic membrane, the presynaptic release of GABA, acting on postsynaptic GABA receptor, inhibitory effect caused by. According to GABA's position and the transfer mode, current characteristics of GABA mediated is not the same. GABA exists in the synapse and synaptic transmission in be-tween, is mediated by Phaisc inhibition (phase inhibition) current. If GABA is present in the synapse, such as the synaptic gap, the gap between the cells, which is mediated by the transfer of the postsynaptic membrane, the inhibition Tonic (tension sup-pression) current. Because the position and the transmission mode of the GABA are different, the phase current and the tension restrain current have their own characteristics. Phase current is intermittent. The characteristics of GABA and tonic inhibition with a persistent current. At the same time, current also has the characteristics of high affinity and low desensitization of GABA tonic suppression, which makes GABA tonic inhibitory currents in the cell potential with than other inhibitory currents are more significant and rapid effect, so the disease occurrence also has important implications for the mechanism. Study on GABA tonic inhibitory current is of great significance to the understanding of neural network, but also can understand the mechanism of the disease, and as a powerful target for the prevention or treatment of diseases.