해마 신경세포에서 흥분성 시냅스 신호전달에 미치는 Brain-derived Neurotrophic Factor의 효과

Abstract

Brain-derived neurotrophic factor (BDNF) rapidly enhances synaptic transmission among the 0ahippocampal neurons in the resting state. This mechanism may be due to the phosphorylation of 0aNMDA receptors through its Trkb receptors on the postsynaptic neuron. In contrast, BDNF also 0ahas a suppressing effect on the synaptic transmission via non-NMDA receptors. The activities of 0anon-NMDA receptors are known to modulate the NMDA receptors activities. This study was to 0ainvestigate, using patch clamp technique, whether the BDNF increases or decreases the 0aglutamate-induced synaptic transmission in which glutamate acts on both NMDA- and non-NMDA 0areceptors. When a postsynaptic neuron was previously excited by a large amount of glutamate, 0aBDNF decreased the synaptic transmission induced by subsequently-applied glutamate. However, 0awhen the signal entered into a postsynaptic neuron was blocked by the application of 0atetrodotoxin, BDNF increased the glutamate-induced responses. These results show that BDNF 0aplays a role in a protection of the neurons against hazardous or uncontrolled activation of 0aglutamate receptors and in an accentuation of the synaptic response when the signal is 0ainevitably diminished.