Delayed S-cone sensitivity losses following the onset of intense yellow backgrounds linked to the lifetime of a photobleaching product?
Delayed S-cone sensitivity losses following the onset of intense yellow backgrounds linked to the lifetime of a photobleaching product?
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强烈的黄色背景出现后，S 锥体敏感性延迟下降与光漂白产品的使用寿命有关吗？
DOI：
10.1167/18.6.12
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发表时间：
2018
影响因子：
1.8
通讯作者：
Stockman A
中科院分区：
文献类型：
--
作者：
Stockman A
30年前，Mollon，Stockman和Polden（1987）报道，在强烈的黄色581-nm背景开始后，S-锥阈值意外地上升了几秒钟，然后恢复到光适应的稳态值-他们称之为“第二类瞬时三盲”（TT 2）。鉴于581 nm光对S-锥细胞几乎没有直接影响，TT 2必须间接地从背景对L-锥细胞和M-锥细胞的影响中产生。我们将这种现象归因于一种未知的L-和M-锥光漂白产物X的作用，X在它们的输出处起作用，就像一种“等同的”背景光，然后抑制S-锥在锥对手的第二个站点。TT 2的时间过程在形式上类似于两阶段一级生化反应A→ X→ C中X的寿命，其连续的最佳拟合时间常数为3.09±0.35和7.73±0.70 s。另外，在最佳拟合时间常数为23.94±1.42 s的情况下，增加一个缓慢恢复的指数“阻尼力”，两阶段的最佳拟合时间常数变为4.15±0.62和6.79±1.00 s。由于时间常数与背景光照以及光异构化速率基本无关，因此A→ X可能是类维生素A循环的一个辅助反应，在漂白速率过高时可能起到缓冲作用。X与S视锥阈值有一定的数学关系，这可能是第一部位适应后对数视锥-对手、第二部位反应压缩的结果。这种压迫力可能是相同的视锥-对手力，它在较暗的黄色背景偏移后，在不寻常的阈值增加后，设定了S-视锥恢复的速率，这种效应被称为“短暂性三盲”（TT 1）。
Thirty years ago, Mollon, Stockman, & Polden (1987) reported that after the onset of intense yellow 581-nm backgrounds, S-cone threshold rose unexpectedly for several seconds before recovering to the light-adapted steady-state value—an effect they called:“transient-tritanopia of the second kind”(TT2). Given that 581-nm lights have little direct effect on S-cones, TT2 must arise indirectly from the backgrounds' effects on the L-and M-cones. We attribute the phenomenon to the action of an unknown L-and M-cone photobleaching product, X, which acts at their outputs like an “equivalent” background light that then inhibits S-cones at a cone-opponent, second-site. The time-course of TT2 is similar in form to the lifetime of X in a two-stage, first-order biochemical reaction A→ X→ C with successive best-fitting time-constants of 3.09±0.35 and 7.73±0.70 s. Alternatively, with an additional slowly recovering exponential “restoring-force” with a best-fitting time-constant 23.94±1.42 s, the two-stage best-fitting time-constants become 4.15±0.62 and 6.79±1.00 s. Because the time-constants are roughly independent of the background illumination, and thus the rate of photoisomerization, A→ X is likely to be a reaction subsidiary to the retinoid cycle, perhaps acting as a buffer when the bleaching rate is too high. X seems to be logarithmically related to S-cone threshold, which may result from the logarithmic cone-opponent, second-site response compression after multiplicative first-site adaptation. The restoring-force may be the same cone-opponent force that sets the rate of S-cone recovery following the unusual threshold increase following the offset of dimmer yellow backgrounds, an effect known as “transient-tritanopia”(TT1).
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影响因子：
--
作者：
EISNER, A;MACLEOD, DIA
通讯作者：
MACLEOD, DIA
影响因子：
1.8
作者：
Golobokova, E. Yu.;Govardovskii, V. I.
通讯作者：
Govardovskii, V. I.
影响因子：
5.5
作者：
ALPERN, M
通讯作者：
ALPERN, M
Π1颜色机制的动态：两个适应位点的进一步证据
DOI：
--
发表时间：
1977
期刊：
Journal of Physiology
影响因子：
--
作者：
E. J. Augenstein;E. Pugh
通讯作者：
E. Pugh
影响因子：
1.8
作者：
A. Watson;J. Nachmias
通讯作者：
J. Nachmias