Comparative quantitative analysis of the cellular composition of the prefrontal cortex in the superorder Cetartiodactyla, using DTI and isotropic fractionator technique.

使用 DTI 和各向同性分馏器技术对鲸鱼总目前额皮质的细胞组成进行比较定量分析。

• 批准号: 240034464
• 负责人: Dr. Nina Patzke
• 金额: --
• 依托单位: Vanderbilt Brain Institute
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/240034464?language=en
• 关键词: Comparative; quantitative; analysis; cellular; composition

Brain size between mammals varies by a factor of approximately 100,000X, with an absolute brain size ranging from less than 0.1g (insectivore) up to 9,000g (sperm whale). The size of the brain is determined by a large variety of factors such as: number of neurons, number of glial cells, cell-body size, dendritic and axonal arborisation as well as by the size of the vascular and ventricular systems. It is often assumed that the neuronal number is determinant for neuronal function and hence for behaviour. Until recently, very little was known about the quantitative cellular composition of mammalian brains; however with the development of the isotropic fractionator techniques the total neuronal and glial number has been examined in 4 different mammalian orders to date. Contrary to the traditional view it seems that the neuronal density does not decrease with increasing brain size, rather the brains scale as order-specific functions of their numbers of neurons. Moreover the glia cell density seems to be relatively constant across species of different orders and does not increase with increasing brain size as was previously assumed.The mammalian superorder Cetartiodactyla is comprised of the even-toed ungulates and the cetaceans, as they share a monophyletic ancestry. Cetartiodactyla contains nearly 300 extant species and is the most diverse order of medium to large bodied mammals, with a large variety in brain and body size, making the species of this superorder the ideal specimens in which to study brain scaling rules. The global aim of the present research proposal is to examine how brain size scales across the mammalian superorder Cetartiodactyl as a function of the numbers of neuronal and glial cells in comparison to the previously examined mammalian orders, using the isotropic fractionator technique. Furthermore we are interested in how these cells are organized in different structures, especially the prefrontal cortex, which will be delineated using MRI/DTI. Such a comparative analysis will give insight into cellular brain scaling rules that are shared between different mammalian orders and therefore might be inherited and retained from a common ancestor and what rules are different and thus might reflect phylogenetic variance across these orders.

哺乳动物之间的大脑大小相差大约100,000倍，大脑的绝对大小从不到0.1克(杀虫剂)到9,000克(抹香鲸)不等。大脑的大小由多种因素决定，例如：神经元的数量、胶质细胞的数量、胞体的大小、树突和轴突的分枝以及血管和脑室系统的大小。人们通常认为神经元的数量是神经元功能的决定因素，因此也是行为的决定因素。直到最近，人们对哺乳动物大脑的定量细胞组成知之甚少；然而，随着各向同性分离技术的发展，到目前为止，已经在4个不同的哺乳动物目中检测了神经元和神经胶质的总数。与传统观点相反，神经元密度似乎并没有随着大脑大小的增加而减少，而是大脑的规模是其神经元数量的特定顺序功能。此外，胶质细胞密度在不同目的物种中似乎相对恒定，并不像以前假设的那样随着大脑大小的增加而增加。哺乳动物超级目鲸目由偶趾有蹄类动物和鲸目动物组成，因为它们都是单系祖先。鲸指目包含近300个现存物种，是中大型体型哺乳动物中种类最多的一个目，其脑部和身体大小变化很大，使该超目物种成为研究脑缩放规律的理想标本。本研究提案的总体目标是使用各向同性分割器技术，与先前研究的哺乳动物目相比，研究哺乳动物超目Cetartiodactyl的脑大小是如何随神经元和神经胶质细胞的数量而变化的。此外，我们对这些细胞如何在不同的结构中组织感兴趣，特别是前额叶皮质，这将通过MRI/DTI来描绘。这种比较分析将深入了解不同哺乳动物目之间共享的细胞脑比例规则，因此可能从共同的祖先继承和保留，以及哪些规则是不同的，从而可能反映这些目之间的系统发育差异。