Contribution of retinal ganglion cells to the mouse electroretinogram

• Published in: Documenta ophthalmologica 2014-06, Vol.128 (3), p.155-168
• Main Authors: Smith, Benjamin J., Wang, Xu, Chauhan, Balwantray C., Côté, Patrice D., Tremblay, François
• Format: Article
• Language: English
• Subjects: 6-Cyano-7-nitroquinoxaline-2,3-dione - toxicity; Animals; Axotomy; Dark Adaptation - physiology; Electroretinography; Excitatory Amino Acid Antagonists - toxicity; Fluorescent Antibody Technique, Indirect; Intravitreal Injections; Medicine; Medicine & Public Health; Mice; Mice, Inbred C57BL; Microscopy, Confocal; Night Vision - physiology; Ophthalmology; Optic Nerve - physiology; Original Research Article; Photic Stimulation; Photoreceptor Cells, Vertebrate - physiology; Receptors, Glutamate - metabolism; Retinal Ganglion Cells - physiology
• ISSN: 0012-4486; 1573-2622
• DOI: 10.1007/s10633-014-9433-2

Purpose To quantify the direct contribution of retinal ganglion cells (RGCs) on individual components of the mouse electroretinogram (ERG). Methods Dark- and light-adapted ERGs from mice 8 to 12 weeks after optic nerve transection (ONTx, n  = 14) were analyzed through stimulus response curves for a- and b-waves, oscillatory potentials (OPs), positive and negative scotopic threshold response (p/n STR), and the photopic negative response (PhNR) and compared with unoperated and sham-operated controls, as well as to eyes treated with 6-cyano-7-nitroquinoxaline-2,3-dion (CNQX). Results We confirmed in mice that CNQX intravitreal injection reduced the scotopic a-wave amplitude at high flash strength, confirming a post-receptoral contribution to the a-wave. We found that ONTx, which is more specific to RGCs, did not affect the a-wave amplitude and implicit time in either photopic or scotopic conditions while the b-wave was reduced. Both the pSTR and nSTR components were reduced in amplitude, with the balance between the two components resulting in a shortening of the nSTR peak implicit time. On the other hand, amplitude of the PhNR was increased while the OPs were minimally affected. Conclusion With an intact a-wave demonstrated following ONTx, we find that the most robust indicators of RGC function in the mouse full-field ERG were the STR components.