Luminance and chromatic signals interact differently with melanopsin activation to control the pupil light response.
Luminance and chromatic signals interact differently with melanopsin activation to control the pupil light response.
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DOI：
10.1167/16.11.29
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发表时间：
2016-09-01
影响因子：
1.8
通讯作者：
Cao D
中科院分区：
文献类型：
--
作者：
Barrionuevo PA;Cao D
固有的光敏性视网膜神经节细胞(IpRGC)表达光色素黑素。这些细胞接受来自视杆和视锥的传入输入，视杆和视锥为后视觉通路提供输入。然而，目前尚不清楚黑素的激活如何与接收后信号相结合来控制瞳孔的光反射。这项研究报告了利用五基色光刺激器产生的刺激测量人类闪烁的瞳孔反应，该五基色光刺激器选择性地单独或联合调制黑色素、视杆细胞、S视锥、M视锥和L视锥的刺激，以产生接收后信号。我们首先分析了黑素激活和视杆细胞和视锥细胞信号的光适应行为。其次，我们通过分别通过大细胞(MC)、黑素细胞(KC)和细小细胞(PC)通路处理的视锥亮度、色度蓝黄和色度红绿刺激来确定黑素如何与受体后信号整合。还测量了视杆和黑素的联合反应。接收后信号的相对相位相对于黑素时相是不同的。结果表明，所有条件下的光适应行为均弱于典型的Weber适应。黑素蛋白的激活与亮度、S锥体和视杆细胞的输入呈线性结合，表明与MC和KC信号的整合部位是视网膜。黑素对时相瞳孔反应的贡献低于亮度贡献，但远高于S锥体贡献。颜色红-绿调制与黑素激活之间的相互作用是非线性的，这是一个“赢家通吃”的过程，这表明与PC信号的整合可能是由视网膜后部位介导的。
Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin. These cells receive afferent inputs from rods and cones, which provide inputs to the postreceptoral visual pathways. It is unknown, however, how melanopsin activation is integrated with postreceptoral signals to control the pupillary light reflex. This study reports human flicker pupillary responses measured using stimuli generated with a five-primary photostimulator that selectively modulated melanopsin, rod, S-, M-, and L-cone excitations in isolation, or in combination to produce postreceptoral signals. We first analyzed the light adaptation behavior of melanopsin activation and rod and cones signals. Second, we determined how melanopsin is integrated with postreceptoral signals by testing with cone luminance, chromatic blue-yellow, and chromatic red-green stimuli that were processed by magnocellular (MC), koniocellular (KC), and parvocellular (PC) pathways, respectively. A combined rod and melanopsin response was also measured. The relative phase of the postreceptoral signals was varied with respect to the melanopsin phase. The results showed that light adaptation behavior for all conditions was weaker than typical Weber adaptation. Melanopsin activation combined linearly with luminance, S-cone, and rod inputs, suggesting the locus of integration with MC and KC signals was retinal. The melanopsin contribution to phasic pupil responses was lower than luminance contributions, but much higher than S-cone contributions. Chromatic red-green modulation interacted with melanopsin activation nonlinearly as described by a “winner-takes-all” process, suggesting the integration with PC signals might be mediated by a postretinal site.
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影响因子：
25
作者：
Altimus, Cara M.;Gueler, Ali D.;Alam, Nazia M.;Arman, A. Cyrus;Prusky, Glen T.;Sampath, Alapakkam P.;Hattar, Samer
通讯作者：
Hattar, Samer
影响因子：
3.5
作者：
al Enezi, Jazi;Revell, Victoria;Lucas, Robert
通讯作者：
Lucas, Robert
影响因子：
1.8
作者：
Cao, Dingcai;Pokorny, Joel;Zele, Andrew J.
通讯作者：
Zele, Andrew J.
影响因子：
64.8
作者：
Dacey, DM;Liao, HW;Gamlin, PD
通讯作者：
Gamlin, PD
DOI：
10.1073/pnas.0401955101
发表时间：
2004-07-06
影响因子：
11.1
作者：
Barton, RA
通讯作者：
Barton, RA