期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2010
卷号：107
期号：1
页码：389-394
DOI：10.1073/pnas.0910986107
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The "One neuron-one neurotransmitter" concept has been challenged frequently during the last three decades, and the coexistence of neurotransmitters in individual neurons is now regarded as a common phenomenon. The functional significance of neurotransmitter coexistence is, however, less well understood. Several studies have shown that a subpopulation of dopamine (DA) neurons in the ventral tegmental area (VTA) expresses the vesicular glutamate transporter 2 (VGLUT2) and has been suggested to use glutamate as a cotransmitter. The VTA dopamine neurons project to limbic structures including the nucleus accumbens, and are involved in mediating the motivational and locomotor activating effects of psychostimulants. To determine the functional role of glutamate cotransmission by these neurons, we deleted VGLUT2 in DA neurons by using a conditional gene-targeting approach in mice. A DAT-Cre/Vglut2Lox mouse line (Vglut2f/f;DAT-Cre mice) was produced and analyzed by in vivo amperometry as well as by several behavioral paradigms. Although basal motor function was normal in the Vglut2f/f;DAT-Cre mice, their risk-taking behavior was altered. Interestingly, in both home-cage and novel environments, the gene targeted mice showed a greatly blunted locomotor response to the psychostimulant amphetamine, which acts via the midbrain DA system. Our results show that VGLUT2 expression in DA neurons is required for normal emotional reactivity as well as for psychostimulant-mediated behavioral activation.
