Dengler C G, Coulter D A
Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; The Research Institute of the Children's Hospital of Philadelphia, Philadelphia, PA, United States.
Prog Brain Res. 2016;226:155-78. doi: 10.1016/bs.pbr.2016.04.005. Epub 2016 May 18.
The dentate gyrus plays critical roles both in cognitive processing, and in regulation of the induction and propagation of pathological activity. The cellular and circuit mechanisms underlying these diverse functions overlap extensively. At the cellular level, the intrinsic properties of dentate granule cells combine to endow these neurons with a fundamental reluctance to activate, one of their hallmark traits. At the circuit level, the dentate gyrus constitutes one of the more heavily inhibited regions of the brain, with strong, fast feedforward and feedback GABAergic inhibition dominating responses to afferent activation. In pathologic states such as epilepsy, a number of alterations within the dentate gyrus combine to compromise the regulatory properties of this circuit, culminating in a collapse of its normal function. This epilepsy-associated transformation in the fundamental properties of this critical regulatory hippocampal circuit may contribute both to seizure propensity, and cognitive and emotional comorbidities characteristic of this disease state.
齿状回在认知加工以及病理活动的诱导和传播调节中都发挥着关键作用。这些不同功能背后的细胞和回路机制广泛重叠。在细胞水平上，齿状颗粒细胞的内在特性共同赋予这些神经元一种基本的激活抗性，这是它们的标志性特征之一。在回路水平上，齿状回是大脑中受抑制程度较高的区域之一，强烈、快速的前馈和反馈GABA能抑制主导着对传入激活的反应。在癫痫等病理状态下，齿状回内的一些改变共同损害了该回路的调节特性，最终导致其正常功能崩溃。这种关键调节性海马回路基本特性的癫痫相关转变可能既导致癫痫发作倾向，也导致该疾病状态特有的认知和情绪共病。
