2009年5月1日,北京生命科学研究所罗敏敏实验室在Neuroscience杂志上在线发表题为“Neurochemical Phenotypes of the Afferent and Efferent Projections of the Mouse Medial Habenula”的文章,该文章报道了伽马氨基丁酸和谷氨酸在小鼠大脑内侧缰核输入和输出投射中的组织形式。
内侧缰核是大脑中连接边缘系统和中脑的重要结构,也是进化中非常保守的结构。早期研究暗示内侧缰核参与调控应激反应和昼夜节律等重要行为,但至今对内侧缰核的输入输出投射通路使用哪些神经递质人们知之甚少。本课题组人员以小鼠作为模式生物,通过结合遗传学标记、神经束示踪和免疫组化等方法,发现内侧隔核和斜角带核为内侧缰核提供抑制性的伽马氨基丁酸输入,三角隔核为内侧缰核提供兴奋性的谷氨酸输入;内侧缰核到角间核的输出投射也能释放谷氨酸。伽马氨基丁酸是大脑中主要的抑制性递质而谷氨酸是主要的兴奋性递质。本研究揭示了这两种重要的神经递质在内侧缰核的输入和输出投射中的组织形式,为将来对这条通路的功能研究提供了基础。
论文的第一作者秦昶是北京生命科学研究所和协和医科大学联合培养的博士生,罗敏敏博士为本文的通讯作者。此项研究由科技部863计划,北京市科委,中国自然科学基金及人类前沿科学计划(HFSP)资助,在北京生命科学研究所完成。(生物谷Bioon.com)
生物谷推荐原始出处:
Neuroscience doi:10.1016/j.neuroscience.2009.03.085
Neurochemical phenotypes of the afferent and efferent projections of the mouse medial habenula
C. Qina, b and M. Luob, c, ,
aGraduate Program in Chinese Academy of Medical Sciences and Peking union Medical College, Beijing, 100730, China
bNational Institute of Biological Sciences, #7 Science Park Road, Zhongguancun Life Science Park, Beijing, 102206, China
cDepartment of Biological Sciences and Biotechnology, Tsinghua University, Beijing, 100084, China
Abstract
The medial habenula (MHb) is a key bridge between limbic forebrain and midbrain monoaminergic centers. Although its exact behavioral function remains enigmatic, it is implicated in regulating many behaviors such as stress responses and circadian rhythm. Fundamental information such as the neurotransmitters in the afferent and efferent projections of the MHb remains unclear. By combining retrograde tract tracing and genetic labeling of GABAergic neurons in mice, we find that the medial septum (MS) and nucleus of diagonal band (NDB) provide GABA-ergic input to the MHb. By anterograde tracing and immunostaining against a marker of glutamatergic synapses, we find that the projection from the triangular septal nucleus (TS) to the MHb has the capacity to release glutamate. This suggests that in addition to ATP, glutamate is another neurotransmitter for the TS→MHb projection. Finally, by combining anterograde tracing and immunostaining, we find that the MHb neurons projecting to the interpeduncular nucleus (IPN) have the capacity to release glutamate. This suggests that, in addition to acetylcholine and substance P, glutamate is another neurotransmitter used by MHb projection neurons. Our findings reveal the organization of two key neurotransmitters for the MHb afferent and efferent projections, and lay framework for future functional studies of this pathway in the brain.