Autonomic nervous systemAutonomic (Visceral) nerve to be concerned with the innervation and control of visceral organs, smooth muscles, cardiac muscles,and gland.Function: homeostasis体内稳态体内稳态 of the internal environment.This is achieved by regulation of cardiovascular, respiratory, digestive, excretory, and thermoregulatory mechanisms.Autonomic (Visceral) nerve1.sensory nerve2.motor nerve sympathetic division parasympathetic division most of the structures are innervated by both most of the structures are innervated by both sympathetic and parasympathetic nerve. One is sympathetic and parasympathetic nerve. One is excitatory and other inhibitory.excitatory and other inhibitory.Autonomic (Visceral) nerveAutonomic efferent neurons - the most remarkable feature There are sequence of There are sequence of two neurons between the CNS neurons between the CNS and the innervated and the innervated structurestructureThe cell body of the first The cell body of the first neuron is located in spinal neuron is located in spinal cord or brainstemcord or brainstemThe cell body of the second neuron The cell body of the second neuron are located in ganglia of sympathetic trunk(chain) or coeliac腹的腹的, superior mesenteric, and inferior mesenteric ganglions or parasympathetic ganglions.the second neuron two neurons between the CNS and the innervated two neurons between the CNS and the innervated structuresstructures Preganglionic & postganglionic fibersPreganglionic & postganglionic fibersSympathetic divisionPreganglionic sympathetic neurons are located in the thoracic 112 and upper two or three lumbar segments of spinal cord.Preganglionic sympathetic neurones lie in the lateral horn T1 12 ,L13 base of anterior horn of spinal cord Sympathetic divisionThe sympathetic ganglia lie in the sympathetic chain of ganglia, or in the coeliac, superior mesenteric, inferior mesenteric ganglia.The postganglionic fibers extends from the peripheral ganglia to the effector organs Sympathetic trunk of thoraxSympathetic trunk of neck The preganglionic fibers innervating the heart terminate in synaptic contact with the postganglionic bodies in the sympathetic trunk of the neck. The postganglionic fibers(superior,middle,and inferior cardiac branches ) travel to cardiac plexuses heart and its vascular vessles pulmonary plexuses- lungs.cardiac plexusescardiac plexuses The preganglionic fibers innervating the eye, lacrimal gland, mucous membranes of nose,palate,parotid gland, submandibular and sublingual gland terminate in synaptic contact with the postganglionic bodies in the sympathetic trunk of neck. The postganglionic fibers run around the arteries ,then distribute to the gland,smooth muscles of the eye Sphincter pupil of the eye-parasympathetic n. Dilator pupil of the eye- sympathetic n.Lacrimal gland Sympathetic trunk of lumbar and sacral The preganglionic fibers innervating the viscera organs The preganglionic fibers innervating the viscera organs in the abdominal and pelvic cavities pass uninterrupted in the abdominal and pelvic cavities pass uninterrupted through sympathetic trunk and travel to through sympathetic trunk and travel to coeliac, superior mesenteric,and inferior mesenteric ganglions. They synaptic contact with the postganglionic bodies in contact with the postganglionic bodies in the ganglia above mentioned .The postganglionic fibers the ganglia above mentioned .The postganglionic fibers travel to CA,SMA,IMA, then distribute travel to CA,SMA,IMA, then distribute to the the to the the viscera organsviscera organs in the abdominal and pelvic cavities in the abdominal and pelvic cavities coeliac, superior mesenateric, and inferior mesenteric gangliasympathetic trunk sympathetic trunk in the abdomen and in the abdomen and pelvispelviscoeliac, superior mesenteric,and inferior mesenteric ganglia. The adrenal肾上腺的 medulla is an exceptional organ in that it is directly innervated by preganglionic sympathetic neuronesParasympathetic divisionThe bodies of the first neurons of parasympathetic division lie in the nucleus of the brain stem and sacral segments of the spinal cord The preganglionic fibers extend from the nucleus of the brain stem and sacral segments of the spinal cord to the peripheral gangliaThe bodies of the second neurons of The bodies of the second neurons of parasympathetic divisionparasympathetic divisionLie in the peripheral ganglia. The parasympathetic cranial division lie beside the organs which it is innervated. The parasympathetic sacral division lie within the organs which it is innervated. The postganglionic fibers extends from the peripheral ganglia to the effector organs Parasympathetic cranial divisionParasympathetic cranial divisionPreganglionic parasympathetic neurones are located in the brain stem and sacral spinal Cord (S24)Within brain stemCell bodies lie in cranial nerve nuclei associated with the oculomotor CN, CN facial glossopharyngeal CN and vagus nerve CN.Sphincter pupil of the eyeSphincter pupil of the eyeDilator pupil of the eyeDilator pupil of the eyeParasympathetic fibers in the facial nerveParasympathetic fibers in the facial nerveParasympathetic fibers in the Parasympathetic fibers in the glossophryngeal Nglossophryngeal N Parasympathetic fibers in the vagus nerveParasympathetic fibers in the sacral divisionOriginates in the base of the anterior horn cells of the second, third, and fourth sacral segments.Axons of these sacral neurons constituting the prepanglionic fibers (or sacral nerve), traverse横过the walls of the descending colon, sigmoid colon, rectus, bladder, and other pelvic visceral organs and terminate in synapse in the ganglion in the wall.The postganglionic distribute to the organs mentioned. Parasympathetic fibers in the sacral divisionParasympathetic fibers in the sacral divisionThe hypothalamus is the subcortex central of autonomic (Visceral) nerveThe limbic is the cortex central of autonomic (Visceral) nerve