神经元和神经胶质细胞-胶质细胞
合集下载
相关主题
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
3. Neurons HAVE synapses that use neurotransmitters. Glial cells do NOT have chemical synapses.
4. Neurons do NOT continue to divide. Glial cells DO continue to divide.
VASTLY underestimated!
• Evidence is mounting:
1. Nurturing role 2. Signaling role (Memory?) 3. Inflammation 4. Pain 5. Many more to come!
Properties of Blood Brain Barriers
3. Selective permeability to molecules based on their molecular weight and lipid solubility
4. Presence of specific 百度文库arkers
• Rich in two enzymes: gamma glutamyl transpeptidase (GGTP) (for amino acid transport) and alkaline phosphatase (transport of phsopahte ions) used as marker for BBB.
Provide the insulation (myelin) to neurons in the peripheral nervous system.
Neuroglia in the CNS
Neuroglia:
Distinguishing Features
• Able to replicate! • Importance in nervous system function is
5. There are many MORE (10-50 times more) glial cells in the brain compared to the number of neurons.
Nerve Cells
Neurons, Glia, Extracellular Space,
and Blood
Provide the insulation (myelin) to neurons in the central nervous system.
Satellite Cells Schwann Cells
Physical support to neurons in the peripheral nervous system.
1. Presence of tight junctions between the endothelial cells
2. One of the notable features of endothelial cells in comparison to other cell is the lack of pinocytic vesicles
• Express receptors for almost all neurotransmitters and neuromodulators
• Increase of intracellular calcium concentration • Membrane depolarization in astrocytes are common
responses to neural activity • Metabolically coupled to neural activity
Types and Functions of Glia
Name of Glial Cell
Astrocyte (Astroglia)
Microglia
Oligodendroglia
Function
Star-shaped cells that provide physical and nutritional support for neurons: 1) clean up brain"debris"; 2) transport nutrients to neurons; 3) hold neurons in place; 4) digest parts of dead neurons; 5) regulate content of extracellular space Like astrocytes, microglia digest parts of dead neurons.
Bidirectional Communication Partners in the CNS
• Receiving signals from neighboring neurons and responding to them with release of neuroactive substances
• Others: glucose transporter (GLUT-1); endothelial barrier antigen (EBA; unknown function) and antigen recognized by the MRC OX-47 monoclonal antibody (important for cell-to-cell adhesion); transferrin receptor (transport of ferric ions).
BBB
Glia are different from neurons:
1. Neurons have TWO "processes" called axons and dendrites. Glial cells only have ONE.
2. Neurons CAN generate action potentials. Glial cells CANNOT, however, do have a resting potential.
4. Neurons do NOT continue to divide. Glial cells DO continue to divide.
VASTLY underestimated!
• Evidence is mounting:
1. Nurturing role 2. Signaling role (Memory?) 3. Inflammation 4. Pain 5. Many more to come!
Properties of Blood Brain Barriers
3. Selective permeability to molecules based on their molecular weight and lipid solubility
4. Presence of specific 百度文库arkers
• Rich in two enzymes: gamma glutamyl transpeptidase (GGTP) (for amino acid transport) and alkaline phosphatase (transport of phsopahte ions) used as marker for BBB.
Provide the insulation (myelin) to neurons in the peripheral nervous system.
Neuroglia in the CNS
Neuroglia:
Distinguishing Features
• Able to replicate! • Importance in nervous system function is
5. There are many MORE (10-50 times more) glial cells in the brain compared to the number of neurons.
Nerve Cells
Neurons, Glia, Extracellular Space,
and Blood
Provide the insulation (myelin) to neurons in the central nervous system.
Satellite Cells Schwann Cells
Physical support to neurons in the peripheral nervous system.
1. Presence of tight junctions between the endothelial cells
2. One of the notable features of endothelial cells in comparison to other cell is the lack of pinocytic vesicles
• Express receptors for almost all neurotransmitters and neuromodulators
• Increase of intracellular calcium concentration • Membrane depolarization in astrocytes are common
responses to neural activity • Metabolically coupled to neural activity
Types and Functions of Glia
Name of Glial Cell
Astrocyte (Astroglia)
Microglia
Oligodendroglia
Function
Star-shaped cells that provide physical and nutritional support for neurons: 1) clean up brain"debris"; 2) transport nutrients to neurons; 3) hold neurons in place; 4) digest parts of dead neurons; 5) regulate content of extracellular space Like astrocytes, microglia digest parts of dead neurons.
Bidirectional Communication Partners in the CNS
• Receiving signals from neighboring neurons and responding to them with release of neuroactive substances
• Others: glucose transporter (GLUT-1); endothelial barrier antigen (EBA; unknown function) and antigen recognized by the MRC OX-47 monoclonal antibody (important for cell-to-cell adhesion); transferrin receptor (transport of ferric ions).
BBB
Glia are different from neurons:
1. Neurons have TWO "processes" called axons and dendrites. Glial cells only have ONE.
2. Neurons CAN generate action potentials. Glial cells CANNOT, however, do have a resting potential.