CAJ | 학술논문

谷氨酸性突触是哺乳动物神经系统的主要兴奋性突触.在正常条件下, 大多数的突触反应是由谷氨酸的AMPA受体传递的.NMDA受体在静息电位下为镁离子抑制.在被激活时, NMDA受体主要参与突触的可塑性变化.但是, 许多NMDA受体拮抗剂在全身或局部注射时能产生行为效应, 提示NMDA受体可能参与静息状态的生理功能.此文中, 我们在离体的前额扣带回脑片上进行电生理记录, 发现NMDA受体参与前额扣带回的突触传递.在重复刺激或近于生理性温度时, NMDA受体传递的反应更为明显.本文直接显示了NMDA受体参与前额扣带回的突触传递, 并提示NMDA受体在前额扣带回中起着调节神经元兴奋的重要作用.
곡안산성돌촉시포유동물신경계통적주요흥강성돌촉.재정상조건하, 대다수적돌촉반응시유곡안산적AMPA수체전체적.NMDA수체재정식전위하위미리자억제.재피격활시, NMDA수체주요삼여돌촉적가소성변화.단시, 허다NMDA수체길항제재전신혹국부주사시능산생행위효응, 제시NMDA수체가능삼여정식상태적생리공능.차문중, 아문재리체적전액구대회뇌편상진행전생리기록, 발현NMDA수체삼여전액구대회적돌촉전체.재중복자격혹근우생이성온도시, NMDA수체전체적반응경위명현.본문직접현시료NMDA수체삼여전액구대회적돌촉전체, 병제시NMDA수체재전액구대회중기착조절신경원흥강적중요작용.
Glutamatergic synapses are common excitatory chemical connections in mammalian central nervous system. At these synapses, most of baseline synaptic transmission is mediated by glutamate AMPA receptors. NMDA receptors that are sensitive to voltage-dependent magnesium blockade selectively contribute to activity-dependent synaptic plasticity. However, inhibition of NMDA receptors by systemic or local administration of NMDA receptor antagonists produced significant effects on different physiological functions that are not believed to depend on NMDA receptor related synaptic plasticity. Here we show that NMDA receptors contribute to synaptic responses in the anterior cingulate cortex (ACC), a region important for cognitive and other brain functions. The contribution of NMDA receptors became more prominent when synapses are stimulated at higher frequencies. Furthermore, at temperatures more close to physiological brain temperatures, more NMDA receptor mediated responses were recorded as compared to the room temperature. These data suggest a new function for NMDA receptors in the ACC as important postsynaptic receptors involved in synaptic transmission, in particular when cells are firing at high frequencies.