Test 6SNS- One motor neuron to the effectorsANSA ganglion is a cluster of cell bodies outside the CNS. An autonomic ganglion is outside the CNS. A Preganglionic neuron is what comes out of the CNS. Its cell body is now in the Lateral Gray Column, not the DRG or the Anterior Gray Column. The Preganglionic neuron leaves the CNS then follows to the Ganglion where it synapses and becomes a Postganglionic neuron. Then the Postganglionic goes to the effector.- Contains 2 motor neurons in the path, known as preganglionic neuron and postganglionic neuron.o Preganglionic neuron- from CNS to autonomic ganglia (outside the CNS). Cell body in the lateral gray horn. Axon runs to the autonomic ganglia.o Postganglionic neuron- from the autonomic ganglia to the effector. Cell body in the autonomic ganglia. Axon runs to the effector.- All of the pathways are motor- NO SENSORY pathways in the ANSo Sensory information provided through the SNS- Autonomic gangliao Sympathetic division Sympathetic chain (vertebral chain, paravertebral)- Cluster of ganglia that lie on the side of the cord. Longitudinal chains parallel to the spinal cord. Prevertebral- Lie anteriorly to the cord, closer to viscera, in the ventral body cavity. Prevertebral just means that it’s in front of the cord.o Parasympathetic division Terminal- Located close to and even perhaps on the effector. Distal end of pathway. Sympathetic Division- Preganglionic neurons arise in the lateral gray horns of the thoracic and lumbar spinal cord segments (T1-L2/3)o Thoracolumbar outflow – Sympathetic Impulses. Refers to the location in the cord that houses their preganglionic neurons. They’re either in the thoracic spinal portion or the lumbar region.1- Rami Communicantes- Sympathetic chain; fourth branch of the spinal nerve. Ramus- breaks away from main body.o White ramus- preganglionic axon goes into the chain; myelinated. Preganglionics are generally shorto Gray ramus- postganglionic axon comes out of the chain Postganglionics are generally long- Superior cervical gangliao Innervates the head. Postganglionics are sent to the head, neck, and face.- Middle cervical gangliao Innervates the heart.- Inferior cervical gangliao Innervates the heart. Postganglionics are sent into the heart.- Thoracolumbar portions: Specific and widespread areas with more distinct innervation.o Thoracic Portion- Thoracic viscera. Heart, lungs, bronchi, middle and upper abdominal viscera.o Lumbar Portion Lower abdominal and pelvic viscera.2- Splanchnic nerves- Preganglionic. Pass through the chain without synapsing and run to the Prevertebral ganglia (other 2nd type of sympathetic pathway). Synapse with Postganglionic after reaching the Prevertebral ganglia.Preganglionic that runs through chain and does not synapse. Greater Splanchnic- Passes through chain, passes through vertebral still Preganglionic, and goes directly to the medullary cells on the kidneys.- Prevertebral ganglia (labeling)- pass through the chain and Prevertebral ganglion, synapse on medullary cells of adrenal glands (kidneys) and release NE into blood; lesser splanchnic from T11does not send adrenal signals to the effector.o Celiac ganglion- passes through Prevertebral and exits Preganglionic and goes all the way to the effector (kidneys).o Aoriticorenal gangliono Renal gangliono Superior mesenteric gangliono Inferior mesenteric ganglion- Greater Splanchnic- pass through the chain AND the Prevertebral ganglia and go all the way to the effector (kidneys) as a Preganglionic neuron. It goes into the Celiac ganglion and from there, some of its fibers stay Preganglionic down to the effector/Adrenal gland of the Kidneys.o The greater splanchnic nerve enters the celiac ganglion and continues to the adrenal gland as a preganglionic neuron.o The Greater Splanchnic has a unique structure- it passes through the chain, passes through the vertebral still Preganglionic, and then passes directly to the kidneys.- General physiologic effects= fight or flighto Increase the activity of the organso The Sympathetic division of ANS- gets body ready to do work. Increases heart rate. Everything builds up.3- White ramus- Branch of spinal nerve that goes into the chain. - Gray ramus- Branch of spinal nerve that comes out of the chain.- Ramii Communicantes- 3 structural variations (shown in picture)o Immediate synapse The Preganglionic takes white ramus to the chain, synapses immediately with the cell body of a postganglionic, post takes the gray ramus and takes the same spinal nerve that the Preganglionic came from, then goes to effector.o Delayed synapse The Preganglionic starts in Lateral Gray Column, either goes up or down one or multiple levels before synapsing, creating the chain itself. White ramus brings the Preganglia in, the message then moves up or down the chain before synapsing with a Postganglionic, which then carries the impulse through the gray ramus through the spinal nerve that is different from the one the Preganglionic entered. Part of the structure that creates the chain.o Prevertebral Ganglion- Structure of a Splanchnic Nerve Not in the chain. Starts in Lateral Gray Column, enters chain through white ramus, doesn’t synapse immediately or delay. The main thing is that it passes through that chain without synapsing. Still Preganglionic. Then it’s in the Prevertebral ganglia where it will synapse with a Postganglionic neuron, which then goes to the effector.4Parasympathetic Division- Preganglionic neurons in cranial III, VII, IX, and X and sacral spinal segments.o Craniosacral outflow- the Preganglionic neurons come out of select Cranial nerves or the sacral spinal segment.o III- Occularmotoro VII- Facialo IX- Glossopharyngealo X- Vagus- the big one in the Parasympathetic division. - Cranial Nerve X (Vagus) produces 80% of parasympathetic impulses.o Goes to the ganglia that lie on the effectors.- The Parasympathetic has no chain. Some Preganglia can be really long because they don’t synapse at all until reaching the viscera.- Sacral portion innervates pelvic viscera (bladder, genitals, and uterus).- General physiologic effects= rest and digest.- Preganglionics enter Terminal Ganglion.- Terminal Ganglia- CN III, VII, and IX go into Terminal Ganglia.o Cilliary ganglion CN III (Occularmotor)- eyes CN III is Cilliary alone.o Pterygopalatine ganglion CN VII (Facial)- submandibular glands, salivary glands.o Submandibular ganglion