autonomic nervous system in detail

1. AUTONOMIC NERVOUS SYTEM

2.  ANS IS AN INVOLUNTARY MOTOR (EFFERENT) SYSTEM
 SUPPLY SMOOTH, CARDIAC MUSCLES & GLANDS
 ACCOMPANIED BY SENSORY (AFFERENT) FIBERS
AUTONOMIC NERVOUS SYSTEM:

3.  CONTROLS INVOLUNTARY ACTIVITIES OF BODY
 LIKE:
 SWEATING
 SALIVATION
 PERISTALSIS
 VASOMOTOR ACTIVITY ETC
AUTONOMIC NERVOUS SYSTEM:

4.  AUTONOMIC NERVES:
 PREGANGLIONIC FIBERS ARISE FROM CNS
 GANGLIA FOR RELAY OF PREGANGLIONIC FIBERS
 POSTGANGLIONIC FIBERS FROM GANGLIA SUPPLY EFFECTORS
 SOMATIC NERVES:
 FROM CNS REACH THEIR DESTINATION WITHOUT ANY DELAY
ANS DIFFERS FROM SOMATIC NS IN

5. ANS DIFFERS FROM SOMATIC NS IN

6.  SYMPATHETIC
 PARASYMPATHETIC
 SYMPATHETIC ACTIVITIES:
 - WIDESPREAD
 - DIFFUSE
 - COMBAT ACUTE EMERGENCIES
 PARASYMPATHETIC ACTIVITIES:
 - DISCRETE
 - ISOLATED
 - PROVIDE A COMFORTABLE ENVIRONMENT
 BOTH ARE IN ABSOLUTE COORDINATION &
 ADJUST BODY INVOLUNTARILY TO GIVEN SURROUNDINGS
DIVISIONS OF AUTONOMIC NS

7. SYMPATHETIC NS
 MAINLY CONCERNED WITH MOBILIZATION OF BODY’S
RESOURCES UNDER STRESS TO INDUCE THE “FIGHT OR
FLIGHT RESPONSE”

8. SYMPATHETIC NS
 THORACOLUMBAR OUTFLOW
 ORIGIN T1 – T12 & LI & L2
SEGMENTS
 FROM LATERAL COLUMNS
 MYELINATED PREGANGLIOINIC
FIBERS (WHITE RAMI)
 EMERGE THROUGH VENTRAL RAMI
WHERE WHITE RAMI ARE
CONNECTED TO SYMPATHETIC
CHAIN GANGLIA
THORACOLUMBAR

9. SYMPATHETIC FIBERS
 PREGANGLIONIC FIBERS
EITHER RELAY IN :
 LATERAL GANGLIA
(SYMPATHETIC CHAIN) OR
 COLLATERAL GANGLIA (CELIAC
GANGLIA)
 NON MYELINATED
POSTGANGLIONIC FIBERS
(GRC) RUN FOR SOME
DISTANCE BEFORE THE
TARGET ORGAN

10. SYMPATHETIC FIBERS
 ADRENAL MEDULA IS SUPPLIED BY
PREGANGLIONIC FIBERS
 SYMPATHETIC FIBERS ARE
ADRENERGIC (NORADRENALIN)
 EXCEPTIONS TO THIS GENERAL
RULE:
 CHOLENERGIC SYMPATHETIC
NERVES:-
 - SWEAT GLANDS
 - SKELETAL MUSCLE VESSELS FOR
VASODILATATION

11. FUNCTIONAL ACTIVITY OF
SYMPATHETIC FIBERS
 VASOMOTOR:
 - VASOCONSTRICTOR
 SUDOMOTOR:
 - SECRETOR OF SWEAT
 PILOMOTOR:
 - ARRECTOR PILI CONTRACTOR

12. FUNCTIONAL ACTIVITY OF
SYMPATHETIC FIBERS
 PUPILARY DILATORS
 PALE FACE
 DRY MOUTH
 TACHYCARDIA
 RISE IN BP
 INHIBITION OF HOLLOW VISCERA
 CLOSURE OF PERINEAL SPHICTORS

13. GENERALIZED
EFFECT
 Blood supply to skeletal
muscles, heart & brain is
markedly increased
 Thus, sympathetic reactions
tend to be ‘mass reactions’,
 Mobilize resources of body for
expenditure of energy in
dealing with emergencies or
emotional crises (fright, fight,
flight)

14. PARASYMPATHETIC NS
 CRANIOSACRAL
OUTFLOW:
 BRAIN:
 3RD, 7TH, 9TH, & 10TH
CRANIAL NERVES
 SACRAL SPINAL
SEGMENTS:
 S2 – S4

15. PARASYMPATHETIC NS
 FUNCTION:
 RESPONSIBLE
SPECIFICALLY FOR
STIMULATION OF
ACTIVIRIES WHEN IN THE
BODY IS AT REST
 CONSERVE THE
RESOURCES OF BODY FOR
LONG LASTING EFFICACY

16. PARASYMPATHETIC FIBERS
 VERY LONG PREGANGLIONIC &
SHORT POSTGANGLIONIC FIBERS
 FIBERS TERMINAL GANGLIA
LOCATED MOSTLY ON VISCERA
 NERVE ENDINGS ARE CHOLINERGIC
(SIMILAR TO SOMATIC NERVE

17. PARASYMPATHETIC ACTIVITY
 FULLY RELAXED SUBJECT
 CONSTRICTED PUPILS
 FACE FLUSHED
 MOIST MOUTH
 PULSE SLOW
 BP LOW
 BLADDER & GUT CONTRACING
 SPHINCTORS RELAXED
 IN GENERAL:
 CONSERVE & RESTORE THE ENERGY RESOURCES OF BODY

18. COMPARISON B/W SYMPATHETIC &
PARASYMPATHETIC SYSTEMS
 SYMPATHETIC:
 THORACOLUMBAR
 SHORT PRE- GANGLIONIC FIBERS RELAY EITHER IN LATERAL OR
COLLATERAL GANGLIS
 POSTGANGLIONIC FIBERS ARE LONG NERVE ENDINGS
 ADRENERGIC EXCEPT SWEAT GLANDS

19. FUNCTION OF SYMPATHETIC NS
 FUNCTIONALLY:
 VASO/ SUDO/ PILOMOTOR
 DILATES SKELETAL Ms BLOOD VESSELS
 SEEN IN SUBJECT EXPOSED TO FEAR & FIGHT
 WIDE & DIFFUSED, TEND TO EXPEND THE ENERGY RESOURCES OF
BODY DURING EMERGENCIES & EMOTIONAL CRISIS

20. FUNCTION OF SYMPATHETIC NS
 SUPPLIES VISCERAL BLOOD VESSELS, SKIN
 AFFERENTS FROM VISCERA & SPECIFIC SKIN AREAS REACH
CEREBRUM THROUGH SPINAL SEGMENT
 SINCE PAIN IS BETTER APPRECIATED FROM SKIN
 IT APPEARS TO BE COMING FROM SKIN RATHER THAN
VISCERA
 THIS IS THE BASIS OF REFFERED PAIN

21. PARASYMPATHETIC NS
 NEURONS FROM:
 BRAIN (CRANIAL) PART:
 CR. NERVE 3RD, 7TH, 9TH, & 10TH
 SPINAL (SACRAL) PART:
 S2—S4
 LONG PRE – GANGLIONIC FIBERS
 TERMINAL GANGLIA MOSTLY ON VISCERA
 SHORT POSTGANGLIONIC FIBERS
 NERVE ENDINGS CHOLINERGIC

22. FUNCTIONS OF PARASYMPATHETIC NS:
 FULLY RELAXED SUBJECT
 NO EFFECT ON SKIN
 DISCRETE, ISOLATED EFFECT,
 CONSERVES & RESTORES THE RESOURCES OF
ENERGY
 SUPPLIES ONLY VISCERA

24. ROLE IN HOMEOSTASIS
IN A NORMAL
SUBJECT THERE IS
A BALANCE B/W
BOTH SYSTEMS TO
MAINTAIN
HOMEOSTASIS

25. THANK YOU