内分泌
词汇介绍
拓展阅读
解析
retinal 英 /ˈretɪnl/ 美 /ˈretɪnl/
释 义 adj. 视网膜的
n. [生化] 视黄醛(等于retinene)
同根词 retina n. [解剖] 视网膜
例 句 If this high concentration of blood sugar continues for a long period, it will affect the vascular system and cause serious diseases including arteriosclerosis and retinal hemorrhages.如果这种高血糖浓度状况持续一段长时期,将影响到血管系统并导致包括动脉硬化和视网膜出血在内的严重疾病。
ganglion 英 /ˈɡæŋɡliən/ 美 /ˈɡæŋɡliən/
释 义 n. [组织] 神经节;[医] 腱鞘囊肿
例 句 But unlike rods and cones, melanopsin ganglion cells send their signals to the part of the brain that regulates the body’s master clock.但是,与前两者不同的是,黑视素神经节细胞将信号传送到负责调节身体主时钟的大脑区域。
cell 英 /sel/ 美 /sel/
释 义 n. 细胞;电池;蜂房的巢室;单人小室
vi. 住在牢房或小室中
n. (Cell)人名;(英)塞尔
同根词 cellularity n. 细胞性;多孔性;细胞结构
例 句 so, essentially, they're establishing or controlling or changing the difference between the charge inside the cell and the charge outside cell.因此本质上来说,它们制造或者控制或者改变,细胞内外电荷之间的电位差。
概述
概述
视网膜神经节细胞(RGC)的大小,连接和对视觉刺激的反应差异很大,但它们都具有长轴突延伸到大脑的决定性特性。这些轴突形成视神经,视交叉和视束。一小部分的视网膜神经节细胞对视力几乎没有或没有任何作用,但它们本身是光敏的。它们的轴突形成视网膜下丘脑束,有助于昼夜节律和瞳孔光反射,从而调节瞳孔的大小。
功能
人的视网膜中约有0.7至150万个视网膜神经节细胞,大约有460万个视锥细胞和9200万个视杆细胞,每个视网膜有9660万个感光器,平均每个视网膜神经节细胞接受约100个视杆和视锥细胞的输入。但是,这些数字在个体之间以及视视网膜位置而异。在中央凹(视网膜中央)中,单个神经节细胞将与少至五个感光器通信,在最外围(视网膜末端),单个神经节细胞将接收来自成千上万个感光器的信息。视网膜神经节细胞在静止时以基本速率自发激发动作电位。激发视网膜神经节细胞会导致放电率增加,而抑制会导致放电率下降。
类型
①W神经节小,占视网膜总视野的40%,由视杆激发,可检测视野中任何地方的方向运动。
②X神经节直径中等,占总直径的55%,视野小,有色觉,持续的反应。
③Y-神经节细胞最大,5%,非常宽的树突状视野,对眼睛的快速运动或光强度的快速变化作出反应,瞬态响应。
线粒体动力学、运输和质量控制: 视神经病变中视网膜神经节细胞活性的瓶颈
发表时间:2017-09-01
影响指数:3.4
作者: Yoko A Ito
期刊:Mitochondrion
The retina is amongst the most metabolically active tissue in the body and, as such, requires a precise regulation of energy production proportional to consumption. Mitochondria play a crucial role in meeting the high metabolic demand of retinal neurons by maintaining a constant energy supply through oxidative phosphorylation. Adenosine triphosphate (ATP) is generated by the electron transport chain complexes located within the cristae folds of the inner mitochondrial membrane (IMM). In addition to energy production, mitochondria are essential for regulating a number of processes essential for neuronal functions including metabolic balance, intracellular calcium homeostasis, production of reactive oxygen species (ROS), and apoptotic signaling. With their high energy demand, complex dendritic arbors, and long axons, it is not surprising that retinal ganglion cells (RGCs) are particularly vulnerable to mitochondrial dysfunction. Indeed, inherited mitochondrial defects are associated with a number of optic neuropathies including Leber’s hereditary optic neuropathy (LHON) and autosomal dominant optic atrophy (ADOA), which are characterized by selective RGC death. Glaucoma, the most common optic neuropathy and the leading cause of irreversible blindness worldwide, has not been linked to mutations that result in mitochondrial dysfunction. However, accumulating evidence indicates that age-related mitochondrial defects play a central role in the pathogenesis of glaucoma.
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