单眼剥夺会导致视觉皮层的同类突触长期抑郁
C D Rittenhouse1, H Z Shouval, M A Paradiso
1Howard Hughes Medical Institute and Department of Neuroscience, Brown University, Providence, Rhode Island 02912, USA.
Nature
|February 9, 1999
概括
在小猫中,短暂剥夺一只眼睛会通过削弱大脑连接而导致持续的视力损失. 剩余的视网膜活动,而不是不活动,驱动这种突触抑郁,支持Bienenstock-Cooper-Munro理论.
科学领域:
- 神经科学是一个神经科学.
- 发育神经科学的发展神经科学.
- 视觉系统可塑性 视觉系统的可塑性
背景情况:
- 早期的视觉体验塑造了皮质发育.
- 单眼剥夺 (MD) 导致持续的视觉皮层功能障碍.
- 比恩斯托克-库珀-蒙罗 (BCM) 理论将突触可塑性与神经元活动联系起来.
研究的目的:
- 为了测试BCM理论的预测,剩余的视网膜活动,而不是不活动,驱动MD诱导的突触抑郁.
- 为了比较盖子接 (自发的视网膜活动) 与毒素 (TTX;不活动) 对视觉皮层反应的影响.
主要方法:
- 小猫视觉皮层发育模型.
- 单眼剥夺通过盖子接.
- 使用眼内四毒素 (TTX) 进行单眼无活化.
- 视觉皮层神经元反应的电生理学评估.
主要成果:
- 与TTX治疗相比,单眼眼皮 suture导致缺失眼睛反应的明显更大的抑郁.
- 这表明MD期间自发的视网膜活动增强了突触抑郁.
- 这些发现支持BCM理论强调活跃的突触机制.
结论:
- 在MD之后的突触抑郁是由剩余的视网膜活动驱动的,而不是完全的不活动.
- 这挑战了视网膜不活动仅仅导致剥夺效应的观念.
- 结果突出了活跃的突触过程在经验依赖的皮质可塑性中的关键作用.
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