生理学——神经系统1.ppt

神经元的一般结构与功能 神经纤维的功能（兴奋传导）与分类 神经纤维冲动传导特征 神经纤维的传导速度 神经纤维的轴浆运输 神经的营养作用及神经营养因子 Cell body(Soma): metabolic center Dendrites: receptive zone Axons: carrying signals to other neurons Axon hillock (initial segment of axon): lowest threshold Axon terminal: output zone, neurotransmitter Classification of neuron Pseudo unipolar By position in reflex arc Afferent or sensory neuron Interneuron or association neuron Efferent or motor neuron By effects on postsynaptic neurons Excitatory neuron: glutamatergic Inhibitory neuron: GABAergic Classification of nerve fibers Myelinated nerve fiber Unmyelinated nerve fiber Myelinated unmyelinated axons On the basis of electrophysiological properties On the basis of released neurotransmitter Axonplasmic transport of neuron Anterograde transport: Fast transport: 250~400 mm/d Slow transport: 1~12 mm/d Retrograde transport: 150~200mm/d Anterograde transport: All necessary proteins are synthesized in the endoplasmic reticulum and Golgi apparatus of the cell body and then transported along the axon to the synaptic knobs by the process of anterograde transport. Retrograde transport: Some of the material taken up at the ending by endocytosis, including nerve growth factor and various viruses, is also transported back to the cell body. Nervous trophic action Neuroglial cell In PNS: Schwann cell In CNS: Astrocyte Oligodendrocyte Microglial cell Ependymal cell Summary Classification of neuron Classification of nerve fibers Characteristics of nerve impulse conduction Factors affecting conducting velocity Axoplasmic transport Nervous trophic action and neurotrophin Neuroglial cells Functions of the nervous system 各种神经胶质细胞的形态与分布模式图 支持、修复和再生：Supporting, Repairing, Regenerative action 物质代谢和营养: Metabolic, Nutritive action 绝缘和屏蔽: Isolating, Barrier actions 维持内环境的稳定: Homeostasis of internal environment 合成、摄取和分泌神经递质: Synthesizing secreting active