Department of Translational Research, University of Pisa, 56123 Pisa, Italy.
Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy.
Int J Mol Sci. 2023 Jul 12;24(14):11346. doi: 10.3390/ijms241411346.
When screening new drugs to treat retinal diseases, ex vivo electroretinography (ERG) potentially combines the experimental throughput of its traditional in vivo counterpart, with greater mechanistic insight and reproducible delivery. To date, this technique was used in experiments with open loop superfusion and lasting up to a few hours. Here, we present a compact apparatus that provides continuous and simultaneous recordings of the scotopic a-waves from four mouse retinas for much longer durations. Crucially, each retina can be incubated at 37 °C in only 2 mL of static medium, enabling the testing of very expensive drugs or nano devices. Light sensitivity and response kinetics of these preparations remain in the physiological range throughout incubation, displaying only very slow drifts. As an example application, we showed that barium, a potassium channel blocker used to abolish the glial component of the ERG, displayed no overt side effects on photoreceptors over several hours. In another example, we fully regenerated a partially bleached retina using a minimal quantity of 9-cis-retinal. Finally, we demonstrated that including antibiotic in the incubation medium extends physiological light responses to over one day. This system represents a necessary stepping stone towards the goal of combining ERG recordings with organotypically cultured retinas.
在筛选治疗视网膜疾病的新药时，离体视网膜电图（ERG）有可能将其传统体内对应物的实验通量与更大的机械洞察力和可重复的传递相结合。迄今为止，这项技术已用于具有开环超滤液和持续数小时的实验中。在这里，我们展示了一种紧凑的设备，可对四个小鼠视网膜的暗视 a 波进行连续和同时记录，持续时间长得多。至关重要的是，每个视网膜可以在仅 2 毫升的静态培养基中在 37°C 下孵育，从而可以测试非常昂贵的药物或纳米设备。这些制剂的光灵敏度和响应动力学在整个孵育过程中仍保持在生理范围内，仅显示出非常缓慢的漂移。作为一个示例应用，我们表明，钡（一种用于消除 ERG 中神经胶质成分的钾通道阻滞剂）在数小时内对光感受器没有明显的副作用。在另一个示例中，我们使用最小量的 9-顺式视黄醛完全再生了部分漂白的视网膜。最后，我们证明在孵育培养基中加入抗生素可以将生理光响应延长至一天以上。该系统是将 ERG 记录与器官型培养的视网膜相结合的目标的必要垫脚石。
