Popova E
Department of Physiology, Medical Faculty, Medical University, 1431, Sofia, Bulgaria,
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2014 May;200(5):333-58. doi: 10.1007/s00359-014-0906-2. Epub 2014 Apr 12.
Dopamine is the most abundant catecholamine in the vertebrate retina. Despite the description of retinal dopaminergic cells three decades ago, many aspects of their function in the retina remain unclear. There is no consensus among the authors about the stimulus conditions for dopamine release (darkness, steady or flickering light) as well as about its action upon the various types of retinal cells. Many contradictory results exist concerning the dopamine effect on the gross electrical activity of the retina [reflected in electroretinogram (ERG)] and the receptors involved in its action. This review summarized current knowledge about the types of the dopaminergic neurons and receptors in the retina as well as the effects of dopamine receptor agonists and antagonists on the light responses of photoreceptors, horizontal and bipolar cells in both nonmammalian and mammalian retina. Special focus of interest concerns their effects upon the diffuse ERG as a useful tool for assessment of the overall function of the distal retina. An attempt is made to reveal some differences between the dopamine actions upon the activity of the ON versus OFF channel in the distal retina. The author has included her own results demonstrating such differences.
多巴胺是脊椎动物视网膜中含量最丰富的儿茶酚胺。尽管视网膜多巴胺能细胞在三十年前就已被描述，但它们在视网膜中的功能仍有许多方面尚不清楚。关于多巴胺释放的刺激条件（黑暗、稳定或闪烁光）以及它对各种类型视网膜细胞的作用，作者们尚未达成共识。关于多巴胺对视网膜总体电活动[反映在视网膜电图（ERG）中]的影响以及其作用所涉及的受体，存在许多相互矛盾的结果。这篇综述总结了目前关于视网膜中多巴胺能神经元和受体类型的知识，以及多巴胺受体激动剂和拮抗剂对非哺乳动物和哺乳动物视网膜中光感受器、水平细胞和双极细胞光反应的影响。特别关注的是它们对弥漫性ERG的影响，这是评估视网膜远端整体功能的有用工具。本文试图揭示多巴胺对视网膜远端ON通道与OFF通道活性作用的一些差异。作者纳入了她自己展示这种差异的研究结果。
