第十四章 神经营养因子 Neurotrophic Factor NTF-神奇的神经元营养品
第十四章 神经营养因子 Neurotrophic Factor NTF-神奇的神经元营养品
简介 在发育的过程中,一个神经元怎样找到它的靶组织? 半个世纪前,发现细胞外的信号能促进神经细胞的 生长、分化。 ·1948年,Bueker首次提出存在NGF。 Rita Levi-Montalcini和Victor Hamburger也证明了 存在着促进这些神经节中神经元生长的可溶性物质。 Levi-Montalcini将一小片含有感觉神经元或交感神 经元的组织放入培养皿中,发现来自肌擅的细胞非 常剧烈地刺激神经突起(neuritic)向外生长
简 介 • 半个世纪前,发现细胞外的信号能促进神经细胞的 生长、分化。 • 1948年,Bueker 首次提出存在NGF。 • Rita Levi-Montalcini和Victor Hamburger也证明了 存在着促进这些神经节中神经元生长的可溶性物质。 • Levi-Montalcini将一小片含有感觉神经元或交感神 经元的组织放入培养皿中,发现来自肌瘤的细胞非 常剧烈地刺激神经突起(neuritic) 向外生长 。 在发育的过程中,一个神经元怎样找到它的靶组织?
(A) (B) Limb bud ablation Spinal cord section 1 week later Ventral horn Missing Normal limb 1934:Victor Hamburger discovered that removal of a limb bud resulted in reduced numbers of sensory and motor neurons in the spinal cord 2001 Sinauer Associates,Inc
3 1934: Victor Hamburger discovered that removal of a limb bud resulted in reduced numbers of sensory and motor neurons in the spinal cord
Based on his limb-bud experiments,V.Hamburger hypothesized that the targets of innervating neurons provide signals that recruit undifferentiated cells to develop into sensory or motor neurons. proposed that target derived signals Taget source ol tieurors ipproach target neurotrohic factor ng neurons.In 1949,Hamburger and bud experiments and found that their aypothesis. 49)J.Exp.Zool.111:457-502. Limited suply of Deceneratng nearon neuotrothic factor 4
4 Based on his limb-bud experiments, V. Hamburger hypothesized that the targets of innervating neurons provide signals that recruit undifferentiated cells to develop into sensory or motor neurons. In 1942, Levi-Montalcini and Levi proposed that target derived signals maintain survival of differentiating neurons. In 1949, Hamburger and Levi-Montalcini repeated the limb bud experiments and found that their results supported the neurotrophic hypothesis. Hamburger, V. and Levi-Montalcini, R. (1949) J. Exp. Zool. 111: 457-502
(C) (D) Transplantation of Effect of Removing or Augmenting Neural supernumerary Targets on the Survival of Related Neurons limb bud Spinal cord section 1 week later Extra Normal limb 1949:Victor Hamburger showed that transplantation of a supernumerary limb resulted in increased numbers of sensory and motor neurons in the spinal cord. 9 2001 Sinauer Associates,Inc
5 1949: Victor Hamburger showed that transplantation of a supernumerary limb resulted in increased numbers of sensory and motor neurons in the spinal cord. Effect of Removing or Augmenting Neural Targets on the Survival of Related Neurons
为什公神经元要依颗自己的靶组织? ·要满足发育中神经系统与其服务的机体的比例 ·所需的神经元的数目要与其靶组织精确的匹配 如何实现? ·脊髓中的这些神经元,与其他的神经元竞争存在于其靶标(肢芽)的 某种资源,而这种资源是有限供应的。 因此,成体神经元的数目并非最初被强硬的遗传决定的,而是可以在 发育的个体中被特殊的神经元-靶组织的相互作用而决定。 6
6 为什么神经元需要依赖自己的靶组织? • 要满足发育中神经系统与其服务的机体的比例 • 所需的神经元的数目要与其靶组织精确的匹配 • 脊髓中的这些神经元,与其他的神经元竞争存在于其靶标(肢芽)的 某种资源,而这种资源是有限供应的。 • 因此,成体神经元的数目并非最初被强硬的遗传决定的,而是可以在 发育的个体中被特殊的神经元-靶组织的相互作用而决定。 如何实现?
(A) (B) 神经元及其靶标的假说: 最小剂量依赖 靶源组织分泌 数量有限 (C) (D) ()suomou 2 0.51510 NGF concentration (ug/ml) Teflon insert separating Neurite Keep NGF in compartment; compartments A,B,and C regression continued proliferation of branches NGF removed from compart- B ments A and B Grease seal Well B Well A WellC Well B Well A Well C 料 NGF NGF NGF No NGF No NGF NGF
7 神经元及其靶标的假说: 最小剂量依赖 靶源组织分泌 数量有限
NGF 1954:neurite outgrowth assay 1960:NGF purified 1969:NGF purified to homogeneity Stanley Cohen Rita Levi-Montalcini 1986:Levi-Montalcini and extract Cohen split the Nobel prize for Physiology or Medicine "for their discovery of growth factors" Academic Press items and derived items 8 copyright 1999 by Academic Press
8 1954: neurite outgrowth assay – extract + extract 1969: NGF purified to homogeneity Stanley Cohen Rita Levi-Montalcini 1986: Levi-Montalcini and Cohen split the Nobel prize for Physiology or Medicine “for their discovery of growth factors” 1960: NGF purified NGF
阐明生长因子和细胞内信号转导级联反应的分子多 样化。 ·生长因子信号转导的失调可能以神经退化疾病为基 础,例如Alzheimer病、Parkinson病、huntington 病和肌萎缩侧面硬化(amyotropic lateral sclerosis)o ·某些神经生长因子为细胞因子
• 阐明生长因子和细胞内信号转导级联反应的分子多 样化。 • 生长因子信号转导的失调可能以神经退化疾病为基 础,例如Alzheimer 病、Parkinson病、huntington 病和肌萎缩侧面硬化( amyotropic lateral sclerosis)。 • 某些神经生长因子为细胞因子
定义 作用于神经系统,影响神经元和神经胶质细 胞生长、分化、存活及其细胞周期的多肽或蛋白 质分子。 神经发育:调节神经元存活 成年神经系统:阻止神经元损伤后的死亡,促进神经元的修复、 轴突再生,调节突触可塑性和神经递质传递 区别:非肽分子,如甾体激素、视黄醛酸和神经 递质
定义 作用于神经系统,影响神经元和神经胶质细 胞生长、分化、存活及其细胞周期的多肽或蛋白 质分子。 神经发育:调节神经元存活 成年神经系统:阻止神经元损伤后的死亡,促进神经元的修复、 轴突再生,调节突触可塑性和神经递质传递 区别:非肽分子,如甾体激素、视黄醛酸和神经 递质