NEUROBIOLOGIC STUDIES OF NEURONS AND GLIA IN CELL CULTURE

细胞培养中神经元和神经胶质细胞的神经生物学研究

• 批准号: 2575594
• 负责人: P G NELSON
• 金额: --
• 依托单位: EUNICE KENNEDY SHRIVER NATIONAL INSTITUTE OF CHILD HEALTH & HUMAN DEVELOPMENT
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2575594
• 关键词: acetylcholine; bioperiodicity; chickens; glia; laboratory mouse; neural information processing; neuromuscular junction; neuronal guidance; neurons; neuropharmacology; neurotrophic factors; receptor; staurosporine; superior colliculus; thrombin; tissue /cell culture; voltage /patch clamp

a) A tissue culture chamber system allows independent electrical activation of each of two sets of cholinergic axons innervating a common population of skeletal muscle cells. Axonal activation produces a loss of synaptic inputs to the muscle as in the case during development in vivo. We have shown previously that the serine protease thrombin plays a critical role in this process of activity dependent synapse reduction or ADSR. We now show that activation of the thrombin receptor by a thrombin receptor activating peptide (TRAP) can produce synapse loss. An analysis of a TRAP analogue, which in other systems is inactive, also fails to produce synapse loss. TRAP action involves activation of a protein kinase and we find that staurosporine, a protein kinase blocker, blocks both TRAP elicited and electrically induced synapse loss. b) Theoretical models of neural networks have suggested that spontaneously active "pacemaker" neurons could be important determinants of network behavior. We have found (using both calcium imaging and patch electrode recordings) that in cultures in which all excitatory synaptic activity is blocked, some 10% or so of neurons exhibit "pacemaker" activity. c) Time lapse microscopy has defined three types of axonal responses to target cells and three categories of guidance molecules are postulated which are differentially distributed amongst tectal (chick) and superior colliculus (mouse) target cells. Neurons in both phyla have repellent cues localized in one particular target region, whereas glia from chick and mouse appear to express qualitatively different classes of guidance cues.

a）组织培养室系统允许独立的电气 激活两组胆碱能轴突中的每一组， 骨骼肌细胞群。 轴突激活会导致 突触输入到肌肉的情况下，在发展过程中， vivo. 我们以前已经表明，丝氨酸蛋白酶凝血酶发挥作用， 在活动依赖性突触减少的过程中， 或ADSR。 我们现在表明，凝血酶受体的激活， 凝血酶受体激活肽（TRAP）可引起突触丢失。 对TRAP类似物的分析，其在其他系统中是无活性的， 无法造成突触缺失TRAP动作涉及激活一个 我们发现星形孢菌素，一种蛋白激酶阻断剂， 阻断TRAP引起的和电诱导的突触丢失。 B） 神经网络的理论模型表明， 活跃的“起搏”神经元可能是网络的重要决定因素 行为 我们发现（使用钙成像和贴片电极 在所有兴奋性突触活动的文化中， 当神经元的活动被阻断时，大约10%左右的神经元表现出“起搏器”活动。 c）、 延时显微镜已经确定了三种类型的轴突反应， 假设靶细胞和三类引导分子 其在顶盖（小鸡）和上级之间差异分布 丘（小鼠）靶细胞。 两门的神经元都有驱避剂 线索定位于一个特定的目标区域，而鸡的神经胶质细胞 和鼠标似乎表达了不同性质的指导类 线索