~BN07 PNS Anatomy.ppt

1,779 views
1,692 views

Published on

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
1,779
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
29
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide
  • Cervical plexus Phrenic nerve: respiratory control Brachial Plexus Lumbar Plexus Sacral Plexus
  • ~BN07 PNS Anatomy.ppt

    1. 1. The Peripheral Nervous System Lecture 7
    2. 2. Peripheral N. S. <ul><li>Cranial Nerves - 12 pair </li></ul><ul><li>Spinal Nerves - 31 pair </li></ul><ul><li>Somatic Division </li></ul><ul><ul><li>Sensory info </li></ul></ul><ul><ul><li>Body Movement </li></ul></ul><ul><li>Autonomic division - Homeostasis </li></ul><ul><ul><li>regulation ~ </li></ul></ul>
    3. 3. Cranial Nerves <ul><li>From ventral surface </li></ul><ul><ul><li>numbered anterior  posterior </li></ul></ul><ul><li>Sensory, motor, or mixed </li></ul><ul><li>Mnemonic ~ </li></ul>
    4. 4. Oh Oh Oh To Touch And Feel Very Green Vegetables A H Olfactory Optic Oculomotor Trochlear Trigeminal Abducens Facial Vestibulococlear Glossopharangeal Vagus Accessory (Spinal) Hypoglossal I II III IV V VI VII VIII IX X XI XII On Old Olympus Towering Top A Famous Vocal German Viewed Some Hops
    5. 5. Spinal Nerves <ul><li>1 pair for each vertebral segment </li></ul><ul><li>8 pr. cervical (C1-C8) </li></ul><ul><li>12 pr. thoracic (T1-T12) </li></ul><ul><li>5 pr. lumbar (L1-L5) </li></ul><ul><li>5 pr. sacral (S1-S5) </li></ul><ul><li>1 pr coccygeal ~ </li></ul>
    6. 6. Spinal Nerves <ul><li>Thoracic nerves relatively small </li></ul><ul><ul><ul><li>back & ribs </li></ul></ul></ul><ul><li>Cervical, lumbar, & sacral: large nerves </li></ul><ul><ul><ul><li>rest of the body </li></ul></ul></ul><ul><li>All Interconnect </li></ul><ul><ul><li>after leaving vertebral canal </li></ul></ul><ul><ul><li>form 4 major plexuses </li></ul></ul><ul><ul><ul><li>cervical, brachial, lumbar, sacral ~ </li></ul></ul></ul>
    7. 7. Somatic Nervous System <ul><li>Sensory input </li></ul><ul><ul><li>receptors  DRG  dorsal SC </li></ul></ul><ul><ul><li>Dorsal column-medial lemniscal pathway </li></ul></ul><ul><ul><li>Spinolthalamic tract </li></ul></ul><ul><li>Motor output </li></ul><ul><ul><li>Receptors  ventral horns  muscles </li></ul></ul><ul><ul><li>Corticospinal tract </li></ul></ul><ul><ul><li>Rubrospinal tract ~ </li></ul></ul>
    8. 8. Dermatomes <ul><li>Sensory innervation </li></ul><ul><ul><li>each spinal nerve has receptive field </li></ul></ul><ul><li>Overlap at distal branches </li></ul><ul><ul><li>redundancy </li></ul></ul><ul><ul><li>retain some sensation even if a complete spinal nerve destroyed ~ </li></ul></ul>
    9. 9. Somatic N.S.: Motor Output
    10. 10. The Lateral Pathway <ul><li>Voluntary movement </li></ul><ul><ul><li>distal limbs </li></ul></ul><ul><ul><li>2 tracts </li></ul></ul><ul><li>Corticospinal tract </li></ul><ul><ul><ul><li>about 1 million axons </li></ul></ul></ul><ul><li>Rubrospinal tract </li></ul><ul><ul><ul><li>small part of pathway ~ </li></ul></ul></ul>
    11. 11. Motor N.S. <ul><li>Striate muscle </li></ul><ul><ul><li>uninterrupted neuron </li></ul></ul><ul><ul><ul><li> motor neuron </li></ul></ul></ul><ul><ul><li>nerve-dependent </li></ul></ul><ul><li>Excitatory only at neuroeffector synapse </li></ul><ul><ul><li>NT is acetylcholine (ACh) </li></ul></ul><ul><ul><ul><li>cholinergic </li></ul></ul></ul><ul><ul><li>Nicotine = direct agonist (AG) </li></ul></ul><ul><ul><li>Curare = direct antagonist (ANT) ~ </li></ul></ul>
    12. 12. Somatic Motor N. S. Spinal Cord Motor Neuron Effector ACh
    13. 13. <ul><li>Homeostasis </li></ul><ul><li>Effectors </li></ul><ul><ul><li>Smooth Muscle </li></ul></ul><ul><ul><li>Cardiac Muscle </li></ul></ul><ul><ul><li>Glands ~ </li></ul></ul>Autonomic N. S.
    14. 14. <ul><li>Not nerve-dependent </li></ul><ul><li>Sympathetic </li></ul><ul><ul><li>Emergency, flight/fight </li></ul></ul><ul><li>Parasympathetic </li></ul><ul><ul><li>Conservation / vegetative ~ </li></ul></ul>Autonomic Subdivisions
    15. 15. Effector Autonomic N. S.: General Features Ganglion Preganglionic neuron Postganglionic neuron
    16. 16. Effector Autonomic N. S.: General Features ACh <ul><li>Nicotinic </li></ul><ul><ul><li>different R-subtype than neuromuscular ~ </li></ul></ul>
    17. 17. Effector Autonomic N. S.: General Features ACh <ul><li>Neuroeffector junction </li></ul><ul><ul><li>Different NT for each division ~ </li></ul></ul>
    18. 18. Pharmacology of Autonomic NS <ul><li>Preganglionic neuron </li></ul><ul><ul><ul><li>releases ACh </li></ul></ul></ul><ul><li>Different NT at effectors </li></ul><ul><ul><li>sympathetic division: NE </li></ul></ul><ul><ul><ul><li>Norepinephrine (or noradrenaline) </li></ul></ul></ul><ul><ul><li>parasympathetic division: ACh ~ </li></ul></ul>
    19. 19. Sympathetic vs. Parasympathetic <ul><li>Sympathetic </li></ul><ul><ul><li>ganglia near spinal cord </li></ul></ul><ul><ul><li>interconnected ---> active together </li></ul></ul><ul><ul><li>long-lasting effects </li></ul></ul><ul><li>Parasympathetic </li></ul><ul><ul><li>ganglia near effector </li></ul></ul><ul><ul><li>discrete ---> active independently </li></ul></ul><ul><ul><li>transient effects </li></ul></ul><ul><li>Antagonistic regulation ~ </li></ul>
    20. 20. Effector Responses <ul><li>Effector Sympathetic Parasympathetic </li></ul><ul><li>Heart + - </li></ul><ul><li>Respiration + - </li></ul><ul><li>GI - + </li></ul><ul><li>Immune system - + </li></ul><ul><li>Sweat glands + no input </li></ul><ul><li>Iris + (radial) + (sphincter) ~ </li></ul>
    21. 21. Parasympathetic Sympathetic ACh Post- Pre- Adrenal Glands Glands Smooth muscle NE
    22. 22. Sympathetic Arousal Syndrome <ul><li>Fight or flight situations </li></ul><ul><ul><li>Diffuse sympathetic activation </li></ul></ul><ul><li>Adrenal glands </li></ul><ul><ul><li>releases NE into blood </li></ul></ul><ul><ul><li>maintains sympathetic arousal </li></ul></ul><ul><li>Parasympathetic rebound </li></ul><ul><ul><li>antagonistic regulation ~ </li></ul></ul>

    ×