Laboratory for Retinal Regeneration, RIKEN Center for Developmental Biology, Kobe, 650-0047, Japan.
Department of Ophthalmology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie, 514-8507, Japan.
Sci Rep. 2016 Aug 2;6:30719. doi: 10.1038/srep30719.
Full-field electroretinograms (ERGs) are used to objectively assess the mass function of the retina, whereas focal ERGs are used to evaluate the focal retinal function. The purpose of this study was to determine the usefulness of a multiple electrode array (MEA) system for recording ex vivo micro ERGs (mERGs) together with multiunit spike responses of the retinal ganglion cells (RGCs) to assess focal retinal function in isolated mouse retinas. The a- and b-waves of the full-field ERGs were present in the mERG. The b-wave was blocked by L-AP4, an inhibitor of the mGluR6 receptor, and the OFF-component was blocked by exposure to PDA, an antagonist of ionotropic glutamate receptors, with a corresponding RGC responses. mERGs were also recorded from mice with progressive retinal degeneration, the C57BL/6J-Pde6b(rd1-2J)/J (rd1) mice, from which conventional full-field ERGs are non-recordable. A blockade of the glutamate receptors indicated that the negative wave of rd1 mice do not originate from the photoreceptors but from the second or third order neurons. This technique of recording mERGs will be useful in assessing the focal properties of the retinas obtained from eyes with pathology and also to follow the recovery of the physiology of the retina in regenerative studies.
全视野视网膜电图（ERG）用于客观评估视网膜的质量功能，而焦点 ERG 用于评估焦点视网膜功能。本研究旨在确定多电极阵列（MEA）系统在记录离体小鼠视网膜中微 ERG（mERG）和视网膜神经节细胞（RGC）的多单位放电反应方面的作用，以评估焦点视网膜功能。mERG 中存在全视野 ERG 的 a 波和 b 波。mGluR6 受体抑制剂 L-AP4 阻断 b 波，离子型谷氨酸受体拮抗剂 PDA 阻断 OFF 成分，同时 RGC 反应也受到抑制。mERG 也从进行性视网膜变性的 C57BL/6J-Pde6b(rd1-2J)/J（rd1）小鼠中记录，这些小鼠的常规全视野 ERG 无法记录。谷氨酸受体的阻断表明，rd1 小鼠的负波不是来自光感受器，而是来自第二或第三级神经元。这种 mERG 记录技术将有助于评估从具有病理学的眼睛获得的视网膜的焦点特性，并且还可以在再生研究中跟踪视网膜生理学的恢复。
