Protocol for tissue clearing and 3D analysis of dopamine neurons in the developing mouse midbrain.
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ABSTRACT:
SUBMITTER: Adolfs Y
PROVIDER: S-EPMC8326876 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Tissue-clearing technologies have developed rapidly in the past decade, especially for use in neuroscience research. We previously reported that CUBIC, which is one tissue-clearing method, is useful for applications in cancer research. CUBIC cancer analysis can be used to detect cancer metastasis with single-cell resolution at whole mouse body/organ level. This approach can also analyze the tumor characteristics with high-quality 3D images. Here, we describe a detailed CUBIC cancer protocol from tissue clearing, capturing 3D images and post-immunohistochemistry. For complete details on the use and execution of this protocol, please refer to Kubota et al. (2017).
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Project description:The rodent ventral tegmental area (VTA) and substantia nigra pars compacta (SNC) contain dopamine neurons intermixed with glutamate neurons (expressing vesicular glutamate transporter 2; VGluT2), which play roles in reward and aversion. However, identifying the neuronal compositions of the VTA and SNC in higher mammals has remained challenging. Here, we revealed VGluT2 neurons within the VTA and SNC of nonhuman primates and humans by simultaneous detection of VGluT2 mRNA and tyrosine hydroxylase (TH; for identification of dopamine neurons). We found that several VTA subdivisions share similar cellular compositions in nonhuman primates and humans; their rostral linear nuclei have a high prevalence of VGluT2 neurons lacking TH; their paranigral and parabrachial pigmented nuclei have mostly TH neurons, and their parabrachial pigmented nuclei have dual VGluT2-TH neurons. Within nonhuman primates and humans SNC, the vast majority of neurons are TH neurons but VGluT2 neurons were detected in the pars lateralis subdivision. The demonstration that midbrain dopamine neurons are intermixed with glutamate or glutamate-dopamine neurons from rodents to humans offers new opportunities for translational studies towards analyzing the roles that each of these neurons play in human behavior and in midbrain-associated illnesses such as addiction, depression, schizophrenia, and Parkinson's disease.
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