Optogenetics has become an indispensable tool for investigating brain functions. Although non-human primates are particularly useful models for understanding the functions and dysfunctions of the human brain, application of optogenetics to non-human primates is still limited. In the present study, we generate an effective adeno-associated viral vector serotype DJ to express channelrhodopsin-2 (ChR2) under the control of a strong ubiquitous CAG promoter and inject into the somatotopically identified forelimb region of the primary motor cortex in macaque monkeys. ChR2 is strongly expressed around the injection sites, and optogenetic intracortical microstimulation (oICMS) through a homemade optrode induces prominent cortical activity: Even single-pulse, short-duration oICMS evokes long-lasting repetitive firings of cortical neurons. In addition, oICMS elicits distinct forelimb movements and muscle activity, which are comparable to those elicited by conventional electrical ICMS. The present study removes obstacles to optogenetic manipulation of neuronal activity and behaviors in non-human primates.

光遗传学已成为研究脑功能必不可少的工具。尽管非人类灵长类动物对于理解人脑的功能和功能异常特别有用，但是光遗传学在非人类灵长类动物中的应用仍然受到限制。在本研究中，我们产生了一个有效的腺相关病毒载体血清型DJ，在强力无所不在的CAG启动子的控制下表达Channelrhodopsin-2（ChR2），并将其注射到猕猴的主要运动皮层的体位识别前肢区域中。ChR2在注射部位周围强烈表达，并且通过自制的光电极通过光遗传学皮层内微刺激（oICMS）诱导了显着的皮层活动：即使是单脉冲，短时间的oICMS也会引起皮层神经元的持久重复放电。此外，oICMS引起明显的前肢运动和肌肉活动，与传统的电子ICMS引起的运动和肌肉活动相当。本研究消除了对非人类灵长类动物神经元活动和行为的光遗传学操纵的障碍。