The autonomic nervous system regulates and controls visceral functions and is composed of the sympathetic and parasympathetic nervous systems. The sympathetic nervous system, which is the larger of the two divisions, is widely distributed throughout the body and prepares the body for emergency situations through effects on cardiac and smooth muscles and glands. It consists of efferent fibers that travel from the spinal cord to sympathetic ganglia, and afferent fibers that travel from visceral organs to the spinal cord without synapsing in the ganglia.

2. SYMPATHATIC NERVOUS
SYSTEM
Dr Iram Tassaduq

4. AUTONOMIC NERVOUS
SYSTEM
The portions of the CENTRAL & PERIPHERAL
nervous system that are concerned primarily
with the regulation & control of visceral
functions are termed collectively the visceral,
vegetative, or autonomic nervous system

5. AUTONOMIC NERVOUS
SYSTEM
 Innervate organs not usually under voluntary control.
 Effectors include cardiac and smooth muscles and
glands.
 Effectors are part of visceral organs and blood vessels.

6. ORGANIZATION OF ANS
 AFFERENT NEURONS
 EFFERENT NEURONS

10. SYMPATHETIC TRUNKS
 Two ganglionated nerve trunks -
paravertebral ganglia
 Extend the whole length of vertebral column
from the cranial base to the coccyx.
 Joined to spinal nerves by rami
communicantes.

14. SYMPATHETIC PART OF ANS
• Larger part
• Widely distributed
• Prepares body for emergency & stress – (fight,
fright & flight)

15. COMPOSITION
Consists of
•Efferents
•Afferents
•Ganglia –
paravertebral &
prevertebral
•Plexuses

17. • Communicating
branches arising
from thoracic and
first two lumbar
spinal nerves
going to
sympathetic
ganglion

18. EFFERENTS
• Cell bodies of
sympathetic neurons
are located in grey
matter of spinal cord.
• Myelinated axons leave
through anterior nerve
root and than pass via
white rami
communicantes to
paravertebral ganglia

19. EFFERENT FIBERS
• Terminate in the
ganglion
• Travel upward to the
cervical region
• Pass through ganglion
without synapsing

23. AFFERENTS
 The afferent myelinated nerve fibers travel
from the viscera through the sympathetic
ganglia without synapsing.
 They reach their cell bodies in the posterior
root ganglion of the corresponding spinal
nerve