CHAPTER 14 AUTONOMIC NERVOUS SYSTEM
AUTONOMIC NERVOUS SYSTEM Organization
Figure 14.1 Place of the ANS in the structural organization of the nervous system. Central nervous system (CNS) Peripheral nervous system (PNS) Sensory (afferent) division Motor (efferent) division Somatic nervous system Autonomic nervous system (ANS) Sympathetic division Parasympathetic division
AUTONOMIC NERVOUS SYSTEM Comparison of Somatic and Autonomic Nervous Systems
AUTONOMIC NERVOUS SYSTEM PARASYMPATHETIC SYMPATHETIC SOMATIC NERVOUS SYSTEM Figure 14.2 Comparison of somatic and autonomic nervous systems. Neuro- Cell bodies in central transmitter Effector nervous system Peripheral nervous system at effector organs Effect Single neuron from CNS to effector organs ACh Heavily myelinated axon Skeletal muscle Two-neuron chain from CNS to effector organs + Stimulatory ACh NE Unmyelinated Ganglion postganglionic axon Lightly myelinated Epinephrine and preganglionic axons norepinephrine ACh Lightly myelinated preganglionic axon Adrenal medulla ACh Ganglion Blood vessel Unmyelinated postganglionic axon ACh Smooth muscle (e.g., in gut), glands, cardiac muscle + Stimulatory or inhibitory, depending on neurotransmitter and receptors on effector organs Acetylcholine (ACh) Norepinephrine (NE)
True or false: All autonomic nervous pathways involve a ganglion. 1) True 2) False
All preganglionic neurons in the autonomic nervous system use which neurotransmitter? 1) Acetylcholine 2) Epinephrine 3) Norepinephrine 4) Can use any of the above
AUTONOMIC NERVOUS SYSTEM Sympathetic and Parasympathetic Nervous Systems
Which of the following is a sympathetic function? 1) Increasing blood pressure 2) Shunting blood to digestive tract 3) Slowing breathing 4) Increasing urine output
AUTONOMIC NERVOUS SYSTEM Anatomy of Sympathetic and Parasympathetic Nervous Systems
Figure 14.3 Overview of the subdivisions of the ANS. Parasympathetic Sympathetic Eye Salivary glands Heart Cervical Brain stem Cranial Sympathetic ganglia Eye Skin* Salivary glands Lungs Lungs T 1 Heart Stomach Thoracic Stomach Pancreas Pancreas L 1 Liver and gallbladder Liver and gallbladder Lumbar Adrenal gland Bladder Genitals Sacral Bladder Genitals
Figure 14.4 Parasympathetic division of the ANS. CN III CN VII CN IX CN X Ciliary ganglion Pterygopalatine ganglion Submandibular ganglion Otic ganglion Eye Lacrimal gland Nasal mucosa Submandibular and sublingual glands Parotid gland Cardiac and pulmonary plexuses Heart Lung Celiac plexus Liver and gallbladder Stomach Pancreas S 2 S 4 Pelvic splanchnic nerves Inferior hypogastric plexus Genitalia (penis, clitoris, and vagina) Rectum Large intestine Small intestine Urinary bladder and ureters Preganglionic Postganglionic Cranial nerve
Figure 14.6 Sympathetic division of the ANS. Eye Lacrimal gland T 1 Pons Superior cervical ganglion Middle cervical ganglion Inferior cervical ganglion Sympathetic trunk (chain) ganglia Cardiac and pulmonary plexuses Nasal mucosa Blood vessels; skin (arrector pili muscles and sweat glands) Salivary glands Heart Lung Greater splanchnic nerve Lesser splanchnic nerve Celiac ganglion Liver and gallbladder L 2 White rami communicantes Sacral splanchnic nerves Superior mesenteric ganglion Lumbar splanchnic nerves Inferior mesenteric ganglion Stomach Spleen Adrenal medulla Kidney Small intestine Large intestine Rectum Preganglionic Postganglionic Genitalia (uterus, vagina, and penis) and urinary bladder
The craniosacral division of the autonomic nervous system is synonymous with the 1) Afferent nervous system 2) Parasympathetic nervous system 3) Somatic nervous system 4) Sympathetic nervous system
Figure 14.5a Sympathetic trunks and pathways. Spinal cord Dorsal root Ventral root Rib Sympathetic trunk ganglion Sympathetic trunk Ventral ramus of spinal nerve Gray ramus communicans White ramus communicans Thoracic splanchnic nerves (a) Location of the sympathetic trunk
Figure 14.5b Sympathetic trunks and pathways (1 of 3). Skin (arrector pili muscles and sweat glands) Lateral horn (visceral motor zone) Dorsal root Dorsal root ganglion Dorsal ramus of spinal nerve Ventral ramus of spinal nerve Gray ramus communicans White ramus communicans To effector 1 Ventral root Sympathetic trunk ganglion Sympathetic trunk Synapse at the same level Blood vessels (b) Three pathways of sympathetic innervation
Figure 14.5b Sympathetic trunks and pathways (2 of 3). Skin (arrector pili muscles and sweat glands) To effector Blood vessels 2 Synapse at a higher or lower level (b) Three pathways of sympathetic innervation
Figure 14.5b Sympathetic trunks and pathways (3 of 3). Splanchnic nerve Collateral ganglion (such as the celiac) Target organ in abdomen (e.g., intestine) 3 Synapse in a distant collateral ganglion anterior to the vertebral column (b) Three pathways of sympathetic innervation
True or false: Ganglia in the sympathetic nervous system are found in effector organs. 1) True 2) False
AUTONOMIC NERVOUS SYSTEM Physiology of Sympathetic and Parasympathetic Nervous Systems
AUTONOMIC NERVOUS SYSTEM Neurotransmitters & receptors
Table 14.2 Cholinergic and Adrenergic Receptors
Which of the following are types of cholinergic receptors? 1) alpha 2) beta 3) muscarinic 4) nicotinic 5) 1 and 2 only 6) 3 and 4 only 7) all of the above
AUTONOMIC NERVOUS SYSTEM Effects of drugs
Table 14.3 Selected Drug Classes That Influence the Activity of the Autonomic Nervous System
Phenylephrine is what kind of drug? 1) sympatholytic 2) sympathomimetic 3) anti-cholinergic 4) acetylcholinesterase inhibitor
AUTONOMIC NERVOUS SYSTEM Interactions between divisions: Tone and reflexes
Figure 14.9 Levels of ANS control. Communication at subconscious level Cerebral cortex (frontal lobe) Limbic system (emotional input) Hypothalamus Overall integration of ANS, the boss Brain stem (reticular formation, etc.) Regulation of pupil size, respiration, heart, blood pressure, swallowing, etc. Spinal cord Urination, defecation, erection, and ejaculation reflexes
True or false: At rest, the sympathetic nervous system is completely off 1) True 2) False
AUTONOMIC NERVOUS SYSTEM Homeostatic imbalances
Beta-blocker medications (b-adrenergic receptor blockers) might be useful for which of the following diseases? 1) Orthostatic hypotension 2) Hypertension 3) Raynaud s disease 4) 2 and 3 only 5) All of the above
AUTONOMIC NERVOUS SYSTEM Role of the adrenal medulla
Which of these chemicals is produced by the adrenal medulla? 1) Acetylcholine 2) Epinephrine 3) Norepinephrine 4) 2 and 3 only 5) All of the above
Table 14.4 Effects of the Parasympathetic and Sympathetic Divisions on Various Organs (1 of 2)
Table 14.4 Effects of the Parasympathetic and Sympathetic Divisions on Various Organs (2 of 2)