Light augments FOS protein induction in brain of short-term enucleated hamsters
Light augments FOS protein induction in brain of short-term enucleated hamsters
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DOI：
10.1016/s0006-8993(01)02330-7
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发表时间：
2001-05
期刊：
影响因子：
2.9
通讯作者：
E. G. Marchant;L. P. Morin
中科院分区：
文献类型：
--
作者：
E. G. Marchant;L. P. Morin
Fos蛋白是在神经元核内合成的一种对各种环境刺激做出反应的蛋白，已被用作刺激特异性脑功能的标志物。本研究旨在探讨紫外线对成年雄性仓鼠几个脑区FOS蛋白免疫反应(FOS-IR)的影响。实验1证实了先前观察到的FOS-IR在视皮层对紫外光的反应。然而，在其他许多区域，蛋白质也被紫外线或白光诱导，在有视力和无核的动物中都有诱导。因此，我们进行了实验，以评估514 nm光对失明或有视力动物FOS-IR诱导的影响。实验2和实验3分别在双侧眼球摘除或假手术后约4天的早期主观夜晚和中期主观白天进行。在实验2中，光和去核独立地和交互地导致FOS-IR神经元核数增加。在实验3中，去核存在主效应，去核与光照条件之间存在交互作用，但不存在光照的主效应。在实验4中，使用60天前摘除核的动物在较早的主观夜晚进行，没有光或摘核的影响。结果支持这样一种观点，即在与主观时间和摘除眼球后的时间相关的特定条件下，光可以通过未知的眼外机制来改变大脑活动。此外，短期摘除本身会引起脑功能的广泛改变，FOS-IR的表达增加表明这一点。这些结果特别不支持视网膜外光接收在直接调节昼夜节律方面的作用。
FOS protein is synthesized in neuronal nuclei in response to a variety of environmental stimuli and has been used as a marker of stimulus-specific brain function. The present studies were initiated to examine the effects of ultraviolet light on the induction of FOS protein immunoreactivity (FOS-IR) in several brain regions of adult male hamsters. Experiment 1 confirmed previous observations of FOS-IR induced in visual cortex in response to ultraviolet light. However, protein was also induced by ultraviolet or white light in a variety of other areas and induction occurred in both sighted and enucleated animals. Therefore, experiments were conducted to evaluate the effects of a 514 nm light on FOS-IR induction in blind or sighted animals. Experiments 2 and 3 were performed during the early subjective night and mid-subjective day, respectively, using animals about 4 days after bilateral enucleation or sham surgery. In Experiment 2, light and enucleation independently and interactively resulted in increased FOS-IR neuronal nuclei counts. In Experiment 3, there was a main effect of enucleation and an interaction between enucleation and light condition, but no main effect of light. In Experiment 4, conducted during the early subjective night using animals enucleated 60 days earlier, there were neither effects of light or enucleation. The results support the view that, under certain conditions related to subjective time of day and time since enucleation, light can act through unknown extraocular mechanisms to modify brain activity. Further, short term enucleation itself induces widespread alteration in brain function as indicated by increased FOS-IR expression. The results specifically do not support a role for extraretinal photoreception with respect to direct circadian rhythm regulation.