Berson David M
Department of Neuroscience, Brown University, Providence, RI 02912, USA.
Trends Neurosci. 2003 Jun;26(6):314-20. doi: 10.1016/S0166-2236(03)00130-9.
A novel photoreceptor of the mammalian retina has recently been discovered and characterized. The novel cells differ radically from the classical rod and cone photoreceptors. They use a unique photopigment, most probably melanopsin. They have lower sensitivity and spatiotemporal resolution than rods or cones and they seem specialized to encode ambient light intensity. Most surprisingly, they are ganglion cells and, thus, communicate directly with the brain. These intrinsically photosensitive retinal ganglion cells (ipRGCs) help to synchronize circadian rhythms with the solar day. They also contribute to the pupillary light reflex and other behavioral and physiological responses to environmental illumination.
最近，一种新型的哺乳动物视网膜光感受器被发现并得到了表征。这种新型细胞与经典的视杆和视锥光感受器截然不同。它们使用一种独特的光色素，很可能是黑视蛋白。它们的敏感度和时空分辨率低于视杆或视锥细胞，似乎专门用于编码环境光强度。最令人惊讶的是，它们是神经节细胞，因此直接与大脑进行通信。这些内在光敏性视网膜神经节细胞（ipRGCs）有助于使昼夜节律与太阳日同步。它们还参与瞳孔光反射以及对环境光照的其他行为和生理反应。
