Roles of the mushroom body in locomotory control in an insect

蘑菇体在昆虫运动控制中的作用

基本信息

批准号：
07640895
负责人：
MIZUNAMI Makoto
金额：
$ 1.41万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

The mushroom body (MB) is the most conspicuous neuropil structure in the insect brain, critical to various forms of associative memory. In order to elucidate the role of the MB in the higher locomotory control, activities of output neurons and the cellular organization of the MB in the cockroach, Periplaneta americana, were studied.1. Activities of MB output neurons of freely behaving cockroaches were examined. Enamel-coated copper wires of 17 mum in diameter were implanted chronically into the MB output neuropil, and unit activity was recorded while the cockroach walked freely in an arena. After the recording, copper ions were impregnated by passing a positive current to reveal profiles of neurons in the vicinity of the electrode tip. The recorded neurons were classified into (1) sensory units which respond to various sensory stimuli, (2) motor-related neurons which are active during locomotory, (3) sensory-motor neurons which are active during sensory stimulation and also during motor action, and (4) neurons whose activity preceded the initiation of specific locomotory action.2. Cellular organization of the cockroach MB was studied by means of reduced-silver and Golgi stainings. I found that two types of repetitive modular subunits with different sizes exist in the MB output neuropil. The first, which I refer to as a sheet, is a thin (1 mum or less) meshwork formed by 200-1000 axons of Kenyon cells. The sheets are further organized into a larger structural grouping, referred to here as a slab, with a width of 3 mum or more. A total of about 30 dark and pale slabs of more or less evenly spaced alternate throughout the length of the output neuropil. I conclude that the MB,insect memory center, consists of two types of repetitive modular subunits, as does the mammalian cerebral cortex.

蘑菇体（MB）是昆虫大脑中最显着的神经纤维结构，对各种形式的联想记忆至关重要。为了阐明MB在高级运动控制中的作用，对美洲大蠊的输出神经元活动和MB的细胞组织进行了研究。 1．检查了自由活动的蟑螂的 MB 输出神经元的活动。直径为 17 微米的搪瓷铜线被长期植入 MB 输出神经纤维中，当蟑螂在竞技场中自由行走时记录单位活动。记录后，通过正电流浸渍铜离子，以显示电极尖端附近神经元的轮廓。记录的神经元分为（1）对各种感觉刺激做出反应的感觉单元，（2）在运动过程中活跃的运动相关神经元，（3）在感觉刺激和运动动作期间活跃的感觉运动神经元， (4) 其活动先于特定运动动作开始的神经元。2．通过还原银染色和高尔基体染色研究了蟑螂 MB 的细胞组织。我发现MB输出神经纤维中存在两种不同大小的重复模块亚基。第一个，我称之为薄片，是由 200-1000 个凯尼恩细胞轴突形成的薄（1微米或更小）网状结构。这些板材进一步组织成更大的结构组，这里称为板，宽度为 3 微米或以上。在输出神经纤维的整个长度上，总共有约 30 个或多或少均匀间隔的深色和浅色板交替。我得出的结论是，MB（昆虫记忆中心）由两种类型的重复模块亚基组成，哺乳动物大脑皮层也是如此。