Autonomic nervous system (ans)
- 1. Saddam Ansari 2nd year Tbilisi State Medical University AUTONOMIC NERVOUS SYSTEM (ANS)
- 2. Introduction Portion of nervous system Regulation of visceral functions Also known as vegetative or involuntary nervous system
- 4. Sympathetic Division Called as thoracolumbar outflow Supplies smooth muscle fibers of visceral organs Blood vessels Heart Lungs Glands Gastrointestinal organs etc.
- 5. Continued… Consists of pre and post ganglionic fiber
- 6. Sympathetic Ganglia Classified into 3 groups 1. Paravertebral or sympathetic chain ganglia 2. Prevertebral or collateral ganglia 3. Terminal or peripheral ganglia
- 8. Sympathetic Chain Ganglia Arrangement- Segmental fashion Location- Anterolateral surface of vertebral column
- 9. Division of Sympathetic chain Ganglia 1.Cervical ganglia-8cervial ganglia into 3 groups • Superior cervical ganglion • Fusion of upper 4 cervical ganglia • Middle cervical ganglion • Fusion of 5th and 6th cervical ganglia • Inferior cervical ganglion • Fusion of 7th and 8th cervical ganglia
- 10. Continued… 2.Thoracic ganglia 12 thoracic ganglia present on each side Preganglionic fibers originates form thoracic segment of spinal cord Postganglionic fibers are distributed into thorax and abdomen
- 12. Continued… 3.Lumbar ganglia • 5 lumbar ganglia • Preganglionic fibers arises form L1 and L2 segments and reach the lumbar ganglia. • Postganglionic fibers supply the abdominal and pelvic organs: • Urinary bladder • Colon etc.
- 13. Continued… 4.Sacral ganglia 5 sacral ganglia Receives preganglionic fibers from L1 and L2 segments Postganglionic fibers innervates blood vessels and sweat glands in lower limb
- 14. Prevertebral or Collateral Ganglia Situated in thorax,abdomen and pelvis Preganglionic fibers arises from T5 to L2 segments Prevertebral ganglia are : Celiac ganglion Superior mesenteric ganglion Inferior mesenteric ganglion
- 16. Terminal or Peripheral Ganglia Situated within or close to structures innervated by them. E.g. heart, bronchi, pancreas and urinary bladder.
- 17. Sympathoadrenergic System Includes sympathetic division and adrenal medulla Adrenal medulla is modified sympathetic ganglion. Increase in sympathetic activity increases the secretion of catecholamines.