光训练和瞳孔光反射是由不同的ipRGCs群体介导的
S-K Chen1, T C Badea, S Hattar
1Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Nature
|July 19, 2011
概括
本质上光敏感的视网膜质细胞 (ipRGCs) 有不同的亚型. Brn3b阴性ipRGCs控制昼夜节律,而Brn3b阳性ipRGCs调节瞳孔光反射 (PLR).
科学领域:
- 神经科学是一个神经科学.
- 眼科医生 眼科 眼科
- 时间生物学 时间生物学
背景情况:
- 本质上光敏感的视网膜质细胞 (ipRGCs) 表达黑色素,对依赖光的功能至关重要.
- ipRGCs调节昼夜光训练和瞳孔光反射 (PLR).
- 以前的研究表明ipRGCs的作用,但缺乏详细的亚种群分析.
研究的目的:
- 基于Brn3b转录因子表达的ipRGCs的不同亚群的研究.
- 为了在功能上区分这些ipRGC亚群及其在光介导反应中的特定作用.
主要方法:
- 利用遗传除技术,选择性地针对ipRGC亚群.
- 检查了大脑中Brn3b阴性和Brn3b阳性ipRGCs的内化模式.
- 评估了选择性除对昼夜光训练和PLR的影响.
主要成果:
- 确定了两个不同的ipRGC亚群:Brn3b阴性M1ipRGC和Brn3b阳性ipRGC.
- Brn3b阴性M1 ipRGCs刺激上神经核 (SCN),这对昼夜节律至关重要.
- Brn3b阳性ipRGCs刺激橄叶前核和其他大脑区域,调解PLR.
- 对Brn3b阳性ipRGCs的选择性切除取消了PLR,但保留了昼夜光训练.
结论:
- ipRGCs由 Brn3b 表达式定义的功能上不同的子群体组成.
- Brn3b阴性M1ipRGCs对于昼夜光训练至关重要.
- Brn3b阳性ipRGCs对于调节瞳孔光反射 (PLR) 来说至关重要.
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