Laboratory of Molecular Genetics, Rockefeller University, New York, NY 10065, USA.
Cell Metab. 2011 Feb 2;13(2):222-32. doi: 10.1016/j.cmet.2010.12.013.
The identity of higher-order neurons and circuits playing an associative role to control feeding is unknown. We injected pseudorabies virus, a retrograde tracer, into masseter muscle, salivary gland, and tongue of BAC-transgenic mice expressing GFP in specific neural populations and identified several CNS regions that project multisynaptically to the periphery. MCH and orexin neurons were identified in the lateral hypothalamus, and Nurr1 and Cnr1 in the amygdala and insular/rhinal cortices. Cholera toxin β tracing showed that insular Nurr1(+) and Cnr1(+) neurons project to the amygdala or lateral hypothalamus, respectively. Finally, we show that cortical Cnr1(+) neurons show increased Cnr1 mRNA and c-Fos expression after fasting, consistent with a possible role for Cnr1(+) neurons in feeding. Overall, these studies define a general approach for identifying specific molecular markers for neurons in complex neural circuits. These markers now provide a means for functional studies of specific neuronal populations in feeding or other complex behaviors.
控制摄食的高级神经元和相关回路的身份尚不明确。我们将表达 GFP 的特定神经元群体的 BAC 转基因小鼠的咬肌、唾液腺和舌部注射伪狂犬病毒（一种逆行示踪剂），鉴定出几个向外周多突触投射的中枢神经系统区域。在下丘脑外侧区鉴定出了 MCH 和食欲素神经元，在杏仁核和岛叶/边缘皮质鉴定出了 Nurr1 和 Cnr1。霍乱毒素β示踪显示，岛叶 Nurr1(+)和 Cnr1(+)神经元分别投射到杏仁核或下丘脑外侧区。最后，我们发现禁食后皮质 Cnr1(+)神经元的 Cnr1mRNA 和 c-Fos 表达增加，提示 Cnr1(+)神经元可能在摄食中起作用。总的来说，这些研究为鉴定复杂神经回路中特定神经元的特定分子标记提供了一种通用方法。这些标记现在为摄食或其他复杂行为中特定神经元群体的功能研究提供了一种手段。
