THE AUTONOMIC NERVOUS SYSTEM

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THE AUTONOMIC NERVOUS SYSTEM
D. C. MIKULECKY PROFESSOR OF PHYSIOLOGY
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ORGANIZATION OF THE NERVOUS SYSTEM
BRAIN SPINAL CORD
CENTRAL NERVOUS SYSTEM (CNS)
AFFERENT NERVES
EFFERENT NERVES
PERIPHERAL NERVOUS SYSTEM
EXTERO- RECEPTORS
INTERO- RECEPTORS
SOMATIC
AUTONOMIC
EFFECTOR ORGANS
SKELETAL MUSCLES
SMOOTH AND CARDIAC MUSCLES AND GLANDS
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THE AUTONOMIC NERVOUS SYSTEM

• TWO NEURON CHAINS
• SYMPATHETIC
• PARASYMATHETIC

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SPINAL CORD
DORSAL HORN
DORSAL
GREY MATTER
DORSAL ROOT GANGLION
LATERAL
VENTRAL HORN
WHITE MATTER
SPINAL NERVE
VENTRAL
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ORGANIZATION OF THE AUTONOMIC NERVOUS SYSTEM
BRAIN
SPINAL CORD
TARGET ORGANS
SYMPATHETIC GANGLIA
PARASYMPATHETIC GANGLIA
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TWO NEURON CHAINS
PRESYNAPTIC NEURON
EFFECTOR ORGAN
SPINE
POSTSYNAPTIC NEURON
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SYMPATHETIC
SYMPATHETIC GANGLIA (NEAR SPINE)
EFFECTOR ORGAN
SPINE
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PARASYMPATHETIC
PARASYMPATHETIC GANGLIA (NEAR EFFECTOR ORGAN)
EFFECTOR ORGAN
SPINE
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AUTONOMIC CONTROL IS IN BRAIN STEM

• HYPOTHALAMUS
• PITUITARY
• PONS
• MEDULLA

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PARASYMPATHETIC

• GANGLION NEAR EFFECTOR ORGAN
• LONG PREGANGLIONIC NEURONS
• SHORT POSTGANGLIONIC NEURONS
• COUCH POTATO
• POSTGANGLIONIC NEURONS ARE CHOLINERGIC
• CRANIAL AND SPINAL NERVES

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SYMPATHETIC

• GANGLION NEAR SPINE
• SHORT PREGANGLIONIC NEURONS
• LONG POSTGANGLIONIC NEURONS
• FLIGHT OR FIGHT
• POSTGANGLIONIC NEURONS ARE ADRENERGIC
• THORACIC AND LUMBAR NERVES

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EFFECTS OF ANS
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DUAL INNERVATION OF MOST VISCERAL ORGANS

• MOST INNERVATED BY BOTH SYSTEMS
• EFFECTS ARE OPPOSITE IN MOST CASES
• TONIC ACTIVITY
• DOMINANCE

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EFFECTS OF POSTSYNAPTIC NEUROTRANSMITTERS

• EPINEPHRINEFLIGHT OR FIGHT REACTION
  (SYMPATHETIC)
• ACETYL CHOLINE COUCH POTATO RESPONSE
  (PARASYMPATHETIC)

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FACTORS AFFECTING THE CONCENTRATION OF NE IN THE
JUNCTIONAL CLEFT

• NEURONAL UPTAKE
• DIFFUSION INTO CAPILARIES
• UPTAKE INTO EFFECTOR CELLS

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ENTERIC SYSTEM

• GI TRACT HAS AN INTRINSIC NERVOUS SYSTEM
• MYENTERIC AND SUBMUCOSAL PLEXUS
• MORE NEURONS THAN IN SPINAL CORD

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THE DIGESTIVE TRACT
Mucosa
Logitudinal Muscle
Submucosal Plexus
Lumen
Circular Muscle
Extrinsic Nerves
Myenteric Plexus
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CONTROL OF DIGESTIVE SYSTEM
External Influences
Local Influences
Receptors in Digestive Tract
Intrinsic Nerve Plexuses
Extrinsic Autonomic Nerves
GI Hormones
Smooth muscle Exocrine Gland Cells Endocrine
Gland Cells