Autonomic nervous system Sympathetic nervous system                                         Dr                            ...
• Autonomic nervous system   -History   -Introduction   -Types :- Sympathetic –Development                         -Introd...
Autonomic Nervous System• Self regulating• History:   – 1898 - J.N.Langley assigned the term Autonomic     Nervous System ...
4
Autonomic Nervous System• Introduction  – Visceral component of    nervous system ,    function closely related    to soma...
Visceral Afferents-Cell bodies –unipolar –   present in cranial sensory or   dorsal root ganglia-Central processes –with  ...
Visceral Efferent• Visceral efferent  pathways in ANS differ  from their somatic  equivalents• pre-ganglionic neurons:   –...
Visceral EfferentsPre-ganglionic              Post-ganglionic                 ganglion                                    ...
• Post-ganglionic neurons –axons are unmyelinated ,  more numerous                                                      9
Subdivisions of ANS• Sympathetic• Parasympathetic• Enteric                                 10
• Sympathetic –mass  response- Constriction of cutaneous  arteries- Cardiac acceleration- Rise in blood pressure- Contract...
Neurotransmitters:• pre-ganglionic neurons of  both are cholinergic• post-ganglionic   – parasympathetic –cholinergic   – ...
Sympathetic Nervous System• Development :--During 5th week, neural crest  cells migrate along sides of  spinal cord gangli...
• Other neural crest cells  migrate to heart, lungs, GIT    terminal ganglia• Axons of sympathetic  neurones in  intermedi...
• Synapse with neurons –  ascend / descend in  sympathetic trunk• Other presynaptic fibers –  pass through paravertebral  ...
Sympathetic Trunk• Two ganglionated nerve  cords –either side of  vertebral column• White & grey rami  communicantes• Loca...
Preganglionic neurones:• Cell bodies of preganglionic  sympathetic neurons –in  lateral horn• Axons –myelinated ,diam  -1....
Behaviour of Preganglionic Fibres• Synapse with neurons in  nearest ganglion or may  ascend or descend• Fibres terminate i...
Postganglionic Neurones of Sympathetic              Nervous System• Somata of postganglionic  neurons –in ganglia of  symp...
Cervical Sympathetic Trunk• B/w Carotid sheath and  prevertebral muscles• Internal carotid nerve• Three cervical ganglia  ...
Superior Cervical Ganglion• Largest ganglion• Lies in front of transverse  processes of C2 and C3  vertebrae• Branches   –...
Middle Cervical Ganglion• Smallest of the Cervical  ganglion• Lies on the C6  vertebra in front or behind  Inf. thyroid ar...
Stellate Ganglion• Formed by the fusion of  C7,C8 andT1 ganglia• Lies b/w neck of 1st Rib and  transverse process of C7  v...
Sympathetic supply – Head and Neck• Preganglionic fibres – T1-T5  segments of Spinal Cord• Ascend in Sympathetic Trunk• Sy...
Thoracic Sympathetic Trunk• Comprises of 11 ganglia• Ganglia lie against the  heads of ribs• Branches   – Grey rami     co...
Coeliac Plexus• Situated around the origin  of coeliac artery• Formed by greater  Splanchnic Nerves and Ist  lumbar sympat...
Lumbar Sympathetic Trunk• Lies retroperitoneally on  the anterolat. surface of  lumbar vertebrae• Rt side – overlapped by ...
Hypogastric Plexuses• Superior hypogastric plexus:-  -location  -formation  -branches• Inferior hypogastric plexus :-  -lo...
Adrenal Medulla• Neural crest cells –  secretary cells of medulla• Sympathetic supply –  preganglionic sympathetic  neuron...
Summary          30
Sympathetic GanglionHistology :• Connective tissue,  ganglion, capsule cells• Nerve cells –multipolar,  smaller• Nucleolus...
Sympathetic Ganglion                       32
Enteric Nervous System• Myenteric (Auerbach’s)  plexus & submucosal  (Meissner) plexus• Plexus –small enteric  ganglia –jo...
Pain Afferents• Sensory neurones –pain  in thoracic & abdominal  organs• Cell bodies –dorsal root  ganglia• Peripheral pro...
• Referred pain –diffuse  localization & radiation• Zone of reference of pain  from int organ coincides  with part of body...
Referred Pain• Heart –middle &  inferior cervical cardiac  nerves, thoracic cardiac  branches of left  sympathetic chain• ...
• Stomach –epigastrium –  Rt & Lt greater splanchnic  nerves• Duodenal ulcer –AAW –  T9 T10• Appendix –lesser  splanchnic ...
Surgical Sympathectomy• Indications   – Peripheral vascular disease –sympathectomy –temporary     vasodilatation –developm...
Upper Thoracic and Cervical                   Sympathectomy• Upper limb -2 & 3 thoracic  ganglia with rami &  intervening ...
Kuntz Nerve• Communicating branch B/w  T1and T2 nerves• Receives Grey rami from  Stellate and T2 ganglia• Clinical relevan...
Lumbar Sympathectomy• Gangliectomy -3 & 4  lumbar ganglia &  intervening trunk• Removal of LI is harmful  – interferes wit...
Horner’s Syndrome• Preganglionic –white ramus  of T1 –sympathetic trunk –  superior cervical ganglion –  postganglionic fi...
Clinical features of   Horner’s syndrome:• Miosis –failure dilation –  unopposed  parasympathetic activity• Partial ptosis...
Central Control of Sympathetic             Nervous System• Hypothalamus –controlling  &integrating center• Hypothalamus –a...
THANK YOU…   45
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2. sympathetic nervous system

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2. sympathetic nervous system

  1. 1. Autonomic nervous system Sympathetic nervous system Dr Swati Patil 1
  2. 2. • Autonomic nervous system -History -Introduction -Types :- Sympathetic –Development -Introduction -Course -Types -Applied 2
  3. 3. Autonomic Nervous System• Self regulating• History: – 1898 - J.N.Langley assigned the term Autonomic Nervous System – 1921 – subdivided ANS into • Sympathetic • Parasympathetic • Enteric 3
  4. 4. 4
  5. 5. Autonomic Nervous System• Introduction – Visceral component of nervous system , function closely related to somatic nervous system – Visceral afferent pathways resemble somatic afferent – Peripheral processes – auotonomic ganglia – somatic nerves 5
  6. 6. Visceral Afferents-Cell bodies –unipolar – present in cranial sensory or dorsal root ganglia-Central processes –with somatic afferents into CNS –establish connections 6
  7. 7. Visceral Efferent• Visceral efferent pathways in ANS differ from their somatic equivalents• pre-ganglionic neurons: – Somata are located in • visceral efferent nuclei & • in lateral grey columns – axons are • myelinated , • pass to peripheral ganglia • synapse with postganglionic neurons 7
  8. 8. Visceral EfferentsPre-ganglionic Post-ganglionic ganglion 8
  9. 9. • Post-ganglionic neurons –axons are unmyelinated , more numerous 9
  10. 10. Subdivisions of ANS• Sympathetic• Parasympathetic• Enteric 10
  11. 11. • Sympathetic –mass response- Constriction of cutaneous arteries- Cardiac acceleration- Rise in blood pressure- Contraction of sphincters- Depression of peristalsis• Sympathetic: mobilization & increased metabolism “fight, flight or fright” or “fight, flight or freeze” 11
  12. 12. Neurotransmitters:• pre-ganglionic neurons of both are cholinergic• post-ganglionic – parasympathetic –cholinergic – sympathetic –nor-adrenergic• principal co-transmitters – ATP , Neuropeptide Y 12
  13. 13. Sympathetic Nervous System• Development :--During 5th week, neural crest cells migrate along sides of spinal cord ganglia - dorsolateral to aorta-Some neural crest cells migrate ventral to aorta pre-aortic ganglia – celiac & mesenteric ganglia 13
  14. 14. • Other neural crest cells migrate to heart, lungs, GIT terminal ganglia• Axons of sympathetic neurones in intermediolateral cell column of thoracolumbar seg of spinal cord pass through ventral root of spinal nerve & white ramus communicans to reach paravertebral ganglia 14
  15. 15. • Synapse with neurons – ascend / descend in sympathetic trunk• Other presynaptic fibers – pass through paravertebral ganglia without synapsing – splanchnic nerves to viscera• Post synaptic fibres –grey rami from sympathetic ganglion into spinal nerve• Sympathetic trunk – ascending & descending fibres 15
  16. 16. Sympathetic Trunk• Two ganglionated nerve cords –either side of vertebral column• White & grey rami communicantes• Location –neck ,thorax, abdomen, pelvis 16
  17. 17. Preganglionic neurones:• Cell bodies of preganglionic sympathetic neurons –in lateral horn• Axons –myelinated ,diam -1.5 - 4 microm• Leave cord in ventral nerve roots – pass into spinal nerves, soon leave in white rami communicants 17
  18. 18. Behaviour of Preganglionic Fibres• Synapse with neurons in nearest ganglion or may ascend or descend• Fibres terminate in single ganglion or through collateral branches – synapse• Fibres may ascend or descend without synapsing –emerge in branches of sympathetic trunk –synapse in ganglia of autonomic plexus 18
  19. 19. Postganglionic Neurones of Sympathetic Nervous System• Somata of postganglionic neurons –in ganglia of sympathetic trunk• Axons –unmyelinated, return to spinal nerve through grey ramus just proximal to white ramus & then form dorsal & ventral ramus 19
  20. 20. Cervical Sympathetic Trunk• B/w Carotid sheath and prevertebral muscles• Internal carotid nerve• Three cervical ganglia – Superior – Middle – Inferior 20
  21. 21. Superior Cervical Ganglion• Largest ganglion• Lies in front of transverse processes of C2 and C3 vertebrae• Branches – Medial – Lateral 21
  22. 22. Middle Cervical Ganglion• Smallest of the Cervical ganglion• Lies on the C6 vertebra in front or behind Inf. thyroid artery• Branches – grey rami communicantes – Cardiac branch – Vascular Branch 22
  23. 23. Stellate Ganglion• Formed by the fusion of C7,C8 andT1 ganglia• Lies b/w neck of 1st Rib and transverse process of C7 vertebra• Branches – Grey rami communicans – Vascular branches 23
  24. 24. Sympathetic supply – Head and Neck• Preganglionic fibres – T1-T5 segments of Spinal Cord• Ascend in Sympathetic Trunk• Synapse in cervical ganglia 24
  25. 25. Thoracic Sympathetic Trunk• Comprises of 11 ganglia• Ganglia lie against the heads of ribs• Branches – Grey rami communicans – Pul. And cardiac Plexus – Splanchnic Nerves 25
  26. 26. Coeliac Plexus• Situated around the origin of coeliac artery• Formed by greater Splanchnic Nerves and Ist lumbar sympathetic nerves• Nerves from the plexus supply abdominal viscera via blood vessels 26
  27. 27. Lumbar Sympathetic Trunk• Lies retroperitoneally on the anterolat. surface of lumbar vertebrae• Rt side – overlapped by IVC• Lt side – overlapped by Aorta• Branches – Splanchnic nerves – Grey rami communicantes 27
  28. 28. Hypogastric Plexuses• Superior hypogastric plexus:- -location -formation -branches• Inferior hypogastric plexus :- -location -formation -branches 28
  29. 29. Adrenal Medulla• Neural crest cells – secretary cells of medulla• Sympathetic supply – preganglionic sympathetic neurons• Secretary cells – postganglionic sympathetic neurons –lack axons or dendrites• Larger secretory cells – secrete adrenaline & NA 29
  30. 30. Summary 30
  31. 31. Sympathetic GanglionHistology :• Connective tissue, ganglion, capsule cells• Nerve cells –multipolar, smaller• Nucleolus –prominent eccentric 31
  32. 32. Sympathetic Ganglion 32
  33. 33. Enteric Nervous System• Myenteric (Auerbach’s) plexus & submucosal (Meissner) plexus• Plexus –small enteric ganglia –joined by thin nerves –unmyelinated• Avascular –nutrition by diffusion• Neurones –excitatory & inhibitory• Afferents to ENS -2 types – cholinergic & NA 33
  34. 34. Pain Afferents• Sensory neurones –pain in thoracic & abdominal organs• Cell bodies –dorsal root ganglia• Peripheral processes – white communicating rami –sympathetic trunk –viscera 34
  35. 35. • Referred pain –diffuse localization & radiation• Zone of reference of pain from int organ coincides with part of body served by somatic sensory neurons assoc with same segment of spinal cord 35
  36. 36. Referred Pain• Heart –middle & inferior cervical cardiac nerves, thoracic cardiac branches of left sympathetic chain• Gall bladder –greater splanchnic nerve , diaphragm –phrenic nerve 36
  37. 37. • Stomach –epigastrium – Rt & Lt greater splanchnic nerves• Duodenal ulcer –AAW – T9 T10• Appendix –lesser splanchnic nerves –T10• Pelvis & ureter –least splanchnic nerves –loin & groin 37
  38. 38. Surgical Sympathectomy• Indications – Peripheral vascular disease –sympathectomy –temporary vasodilatation –development of collaterals – Hyperhidrosis –sympathectomy –permanent relief – Relief of Pain –a) visceral pain –excision / destruction – coeliac ganglia –Ca pancreas, chronic pancreatits – b) causlgia –intense pain 38
  39. 39. Upper Thoracic and Cervical Sympathectomy• Upper limb -2 & 3 thoracic ganglia with rami & intervening part• 1st thoracic –not removed, preganglionic fibres not arise above T2 (removal – Horner’s syndrome) 39
  40. 40. Kuntz Nerve• Communicating branch B/w T1and T2 nerves• Receives Grey rami from Stellate and T2 ganglia• Clinical relevance –failure to identify during thoracic sympathectomy 40
  41. 41. Lumbar Sympathectomy• Gangliectomy -3 & 4 lumbar ganglia & intervening trunk• Removal of LI is harmful – interferes with ejaculation 41
  42. 42. Horner’s Syndrome• Preganglionic –white ramus of T1 –sympathetic trunk – superior cervical ganglion – postganglionic fibres (ICA) – ophthalmic –nasociliary – long ciliary branches• Damage –vascular lesions of cortex / brainstem, cervical rib, Ca lung, thyroid, oesophagus 42
  43. 43. Clinical features of Horner’s syndrome:• Miosis –failure dilation – unopposed parasympathetic activity• Partial ptosis –paralysis of LPS• Anhydrosis –lesion of superior cervical ganglion 43
  44. 44. Central Control of Sympathetic Nervous System• Hypothalamus –controlling &integrating center• Hypothalamus –autonomic nuclei –spinal cord – reticular formation• Posterior & lateral nuclei – noradrenergic response 44
  45. 45. THANK YOU… 45

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