02 neurons ma
-
Upload
saurabh-kashyap -
Category
Education
-
view
159 -
download
1
Transcript of 02 neurons ma
![Page 1: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/1.jpg)
1) General properties common to all cell types
2) Special properties of glia
3) Special properties of neurons
![Page 2: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/2.jpg)
As all other cell types neurons contain many organelles:
Ribosomes (protein synthesis)
Golgi apparatus(post-transcriptional modification,glycosylation)
Endoplasmic reticulum (Ca buffer)
Mitochondria(energy dispensing)
Lysosomes(protein recycling)
![Page 3: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/3.jpg)
Cell = workshop
Neurons (and glias as well) are not stable entities but rather a continuously changing environment:
Lipids in the membrane are in a liquid rather than solid phase.
Membrane proteins that are not bound to an anchoring cytoskeleton protein literally “swim” in the membrane.
Membrane proteins are being continuously endocytized, destroyed in the lysosomes and re-synthesized
The stability of the human memory, behavior and learning is not explained at the cellular level.
![Page 4: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/4.jpg)
![Page 5: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/5.jpg)
![Page 6: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/6.jpg)
![Page 7: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/7.jpg)
![Page 8: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/8.jpg)
Calcium stores• Extracellular [Ca]o ≈ 10-3 M Intracellular [Ca]i ≈ 10-8M !!!• The endoplasmic reticulum (ER) and mitochondria have a
higher [Ca+2] compared with the cytoplasm.
• The ER has two pharmacologically different Ca+2 stores, both of which are opened by physiological cellular events: one by the activation of IP3 metabolism (PLC) and the other one by elevation of cytosolic Ca+2 itself (Ryanodine-store) and is related to muscle cysternae
• Mitochondria are a slow Ca+2 buffer
![Page 9: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/9.jpg)
[Ca+2]i regulates:
• V-gated channel gating and kinetics
• Ligand-gate channel gating and kinetics
• Gene expression
• Second messenger activation
![Page 10: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/10.jpg)
Glia
![Page 11: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/11.jpg)
Although neurons are the most studied constituents of the nervous system,
![Page 12: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/12.jpg)
Glial Cells, are the most abundantFunctions: maintain ionic balance, transmitter uptake, recovery from injury, modulate rate of AP propagation
- Astrocyte - Microglia - Oligodendrocyte - Schwann cell
![Page 13: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/13.jpg)
Oligodendrocyte
Oligodendrocyte
![Page 14: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/14.jpg)
![Page 15: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/15.jpg)
![Page 16: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/16.jpg)
Schwann cell
![Page 17: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/17.jpg)
![Page 18: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/18.jpg)
Radial Glia
![Page 19: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/19.jpg)
Neurons
AnatomyVs.Physiology
![Page 20: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/20.jpg)
Electron Microscopy of Neuron Cell Body
![Page 21: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/21.jpg)
Cell Types
• Unipolar Cell
• Bipolar Cell
• Pseudo-unipolar Cell
• Multi-polar Cells
![Page 22: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/22.jpg)
Structural proteins
![Page 23: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/23.jpg)
Cellular transport: anterograde and retrograde
![Page 24: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/24.jpg)
Electron Microscopy
of the Synapse
![Page 25: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/25.jpg)
3-D Reconstruction of Dendritic Spines
![Page 26: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/26.jpg)
How is the signal transmitted from one point to another within a neuron?
Answer:by a transient change in electric field and associated voltage
![Page 27: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/27.jpg)
![Page 28: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/28.jpg)
Membrane Potential
- maintained by Na+-K+ pump
- Depolarization = excitatory- Hyperpolarization
= inhibitory
![Page 29: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/29.jpg)
Action Potential
100 millivolt amplitude1 millisecond duration
Hodgkin and Huxley, 1939
Electric properties of the neurons
![Page 30: 02 neurons ma](https://reader034.fdocuments.in/reader034/viewer/2022052323/558c9028d8b42a08438b464d/html5/thumbnails/30.jpg)
Neuron-neuron communication is mediated by synapses