Peripheral nervous system--autonomic nervous division

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Peripheral nervous system--autonomic nervous
division
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What does the ANS do?

• AKA the visceral motor system
• Unconsciously controls/modulates basic body
  functions (homeostasis)
• Body temperature
• Digestion
• Heart rate
• Metabolism
• Breathing
• Defecation/urination
• Pupil diameter

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What parts make up the SNS?

• SNS nerves arise from thoracic and lumbar regions
  of spinal cord
• Often called the thoracolumbar division
• Adrenal glands closely associated
• Adrenal medulla is modified sympathetic ganglion
• Secrete
• E (epinephrine, AKA adrenaline)
• NE (norepinephrine, AKA noradrenaline)

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What parts make up the PNS?

• PNS nerves arise from brain and sacral regions of
  spinal cord
• Often called the craniosacral division
• Leave brainstem by four cranial nerves
• Oculomotor (III), glossopharyngeal (IX), facial
  (VII) and vagus (X)

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What is the enteric nervous system?

• Plexus (net) of about 100 M neurons in wall of
  digestive tract
• Regulates motility, secretion
• Both SNS and PNS help regulate
• Still fairly independent, however

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What are adrenergic receptors?

• Two types of receptor cells
• Alpha- (?) adrenergic receptors
• Usually NE excites
• Beta- (?) adrenergic receptors
• Usually NE inhibits
• Beta-blockers such as propranolol