Faculty of Life Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
Cell Mol Life Sci. 2010 Jan;67(1):99-111. doi: 10.1007/s00018-009-0155-7. Epub 2009 Oct 29.
Over the last ten years there has been growing acceptance that retinal photoreception among mammals extends beyond rods and cones to include a small number of intrinsically photosensitive retinal ganglion cells (ipRGCs). These ipRGCs are capable of responding to light in the absence of rod/cone input thanks to expression of an opsin photopigment called melanopsin. They are specialised for measuring ambient levels of light (irradiance) for a wide variety of so-called non-image-forming light responses. These include synchronisation of circadian clocks to light:dark cycles and the regulation of pupil size, sleep propensity and pineal melatonin production. Here, we provide a review of some of the landmark discoveries in this fast developing field, paying particular emphasis to recent findings and key areas for future investigation.
在过去的十年中，人们越来越接受这样一种观点，即哺乳动物的视网膜光感受器不仅包括杆状细胞和锥状细胞，还包括少量内在光敏性视网膜神经节细胞（ipRGCs）。这些 ipRGCs 由于表达一种叫做黑视蛋白的光感受色素 opsin，能够在没有杆状细胞/锥状细胞输入的情况下对光作出反应。它们专门用于测量各种所谓的非成像光反应的环境光水平（辐照度）。这些反应包括生物钟与光暗周期的同步以及瞳孔大小、睡眠倾向和松果腺褪黑素产生的调节。在这里，我们回顾了这一快速发展领域中的一些具有里程碑意义的发现，特别强调了最近的发现和未来研究的关键领域。
