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Sympathetic Ganglion
The sympathetic ganglia, or paravertebral ganglia, are autonomic ganglia of the sympathetic nervous system. Ganglia are 20,000 to 30,000 afferent and efferent nerve cell bodies that run along on either side of the spinal cord. Afferent nerve cell bodies bring information from the body to the brain and spinal cord, while efferent nerve cell bodies bring information from the brain and spinal cord to the rest of the body. The cell bodies create long sympathetic chains that are on either side of the spinal cord. They also form para- or pre-vertebral ganglia of gross anatomy. The efferent nerve cell bodies bring information from the body to the brain regarding perceptions of danger. This perception of danger can instigate the fight-or-flight response associated with the sympathetic nervous system. The fight-or-flight response is adaptive when there is a real and present danger which can be avoided or diminished through increased sympathetic activity. Sympathetic activity could be incr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympathetic Nervous System
The sympathetic nervous system (SNS or SANS, sympathetic autonomic nervous system, to differentiate it from the somatic nervous system) is one of the three divisions of the autonomic nervous system, the others being the parasympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of the autonomic nervous system, and sometimes considered an independent system. The autonomic nervous system functions to regulate the body's unconscious actions. The sympathetic nervous system's primary process is to stimulate the body's fight or flight response. It is, however, constantly active at a basic level to maintain homeostasis. The sympathetic nervous system is described as being antagonistic to the parasympathetic nervous system. The latter stimulates the body to "feed and breed" and to (then) "rest-and-digest". The SNS has a major role in various physiological processes such as blood glucose levels, body temperature, cardiac output, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cervical Ganglia
The cervical ganglia are paravertebral ganglia of the sympathetic nervous system. Preganglionic nerves from the thoracic spinal cord enter into the cervical ganglions and synapse with its postganglionic fibers or nerves. The cervical ganglion has three paravertebral ganglia: * superior cervical ganglion (largest) – adjacent to C2 & C3; postganglionic axon projects to target: (heart, head, neck) via "hitchhiking" on the carotid arteries * middle cervical ganglion (smallest) – adjacent to C6; target: heart, neck * inferior cervical ganglion The inferior cervical ganglion is one of the three cervical sympathetic ganglia (i.e. of the cervical portion of the sympathetic trunk). It is situated between the base of the transverse process of the last cervical vertebra and the neck of the .... The inferior ganglion may be fused with the first thoracic ganglion to form a single structure, the stellate ganglion. – adjacent to C7; target: heart, lower neck, arm, posterior crani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Mesenteric Ganglia
The superior mesenteric ganglion is a ganglion in the upper part of the superior mesenteric plexus. It lies close to the origin of the superior mesenteric artery. Structure The superior mesenteric ganglion is the synapsing point for one of the pre- and post-synaptic nerves of the sympathetic division of the autonomic nervous system. Specifically, contributions to the superior mesenteric ganglion arise from the lesser splanchnic nerve, which typically arises from the spinal nerve roots of T10 and T11. This nerve goes on to innervate the jejunum, the ileum, the ascending colon and the transverse colon. While the sympathetic input of the midgut is innervated by the sympathetic nerves of the thorax, parasympathetic innervation is done by the vagus nerve The vagus nerve, also known as the tenth cranial nerve (CN X), plays a crucial role in the autonomic nervous system, which is responsible for regulating involuntary functions within the human body. This nerve carries both sens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celiac Ganglia
The celiac ganglia or coeliac ganglia are two large irregularly shaped masses of nerve tissue in the upper abdomen. Part of the sympathetic subdivision of the autonomic nervous system (ANS), the two celiac ganglia are the largest ganglia in the ANS, and they innervate most of the digestive tract. They have the appearance of lymph glands and are placed on either side of the midline in front of the crura of the diaphragm, close to the suprarenal glands (also called adrenal glands). The ganglion on the right side is placed behind the inferior vena cava. They are sometimes referred to as the semilunar ganglia or the solar ganglia. Neurotransmission The celiac ganglion is part of the sympathetic prevertebral chain possessing a great variety of specific receptors and neurotransmitters such as catecholamines, neuropeptides, and nitric oxide and constitutes a modulation center in the pathway of the afferent and efferent fibers between the central nervous system and the ovary. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelvis
The pelvis (: pelves or pelvises) is the lower part of an Anatomy, anatomical Trunk (anatomy), trunk, between the human abdomen, abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis or pelvic skeleton). The pelvic region of the trunk includes the bony pelvis, the pelvic cavity (the space enclosed by the bony pelvis), the pelvic floor, below the pelvic cavity, and the perineum, below the pelvic floor. The pelvic skeleton is formed in the area of the back, by the sacrum and the coccyx and anteriorly and to the left and right sides, by a pair of hip bones. The two hip bones connect the spine with the lower limbs. They are attached to the sacrum posteriorly, connected to each other anteriorly, and joined with the two femurs at the hip joints. The gap enclosed by the bony pelvis, called the pelvic cavity, is the section of the body underneath the abdomen and mainly consists of the reproductive organs and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abdomen
The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal cavity. In arthropods, it is the posterior (anatomy), posterior tagma (biology), tagma of the body; it follows the thorax or cephalothorax. In humans, the abdomen stretches from the thorax at the thoracic diaphragm to the pelvis at the pelvic brim. The pelvic brim stretches from the lumbosacral joint (the intervertebral disc between Lumbar vertebrae, L5 and Vertebra#Sacrum, S1) to the pubic symphysis and is the edge of the pelvic inlet. The space above this inlet and under the thoracic diaphragm is termed the abdominal cavity. The boundary of the abdominal cavity is the abdominal wall in the front and the peritoneal surface at the rear. In vertebrates, the abdomen is a large body cavity enclosed by the abdominal muscles, at the front an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Splanchnic Nerves
The splanchnic nerves are paired visceral nerves (nerves that contribute to the innervation of the internal organs), carrying fibers of the autonomic nervous system ( visceral efferent fibers) as well as sensory fibers from the organs ( visceral afferent fibers). All carry sympathetic fibers except for the pelvic splanchnic nerves, which carry parasympathetic fibers. Types The term ''splanchnic nerves'' can refer to: * Cardiopulmonary nervesEssential Clinical Anatomy. K.L. Moore & A.M. Agur. Lippincott, 3 ed. 2007. Page 181 * Thoracic splanchnic nerves (greater, lesser, and least) * Lumbar splanchnic nerves * Sacral splanchnic nerves * Pelvic splanchnic nerves See also * Terminal cisterna * Rexed lamina * Preganglionic nerve fiber * Postganglionic nerve fiber In the autonomic nervous system, nerve fibers from the ganglion to the effector organ are called postganglionic nerve fibers. Neurotransmitters The neurotransmitters of postganglionic fibers differ: * In t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prevertebral Ganglia
Prevertebral ganglia (or collateral ganglia, or preaortic ganglia) are sympathetic ganglia situated along the midline, anterior to the aorta and the vertebral column. The prevertebral ganglia are the celiac ganglia (including the aorticorenal ganglia), the superior mesenteric ganglion, and the inferior mesenteric ganglion. The paravertebral ganglia, meanwhile, are the segmental ganglia of each the sympathetic trunk situated along either side of the midline. See also * Autonomic ganglion * Prevertebral plexus * Dogiel cells Dogiel cells, also known as cells of Dogiel, are a type of multipolar neuronal cells within the prevertebral sympathetic ganglia. They are named after the Russian anatomist and physiologist Alexandre Dogiel (1852–1922). Dogiel cells play a r ... Additional images File:Gray839.png, Sympathetic (red) and parasympathetic (blue) nervous system References External links * {{Autonomic Sympathetic nervous system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiac Plexus
The cardiac plexus is a plexus of nerves situated at the base of the heart that innervates the heart. Structure The cardiac plexus is divided into a superficial part, which lies in the concavity of the aortic arch, and a deep part, between the aortic arch and the trachea. The two parts are, however, closely connected. The sympathetic component of the cardiac plexus comes from cardiac nerves, which originate from the sympathetic trunk. The parasympathetic component of the cardiac plexus originates from the cardiac branches of the vagus nerve. Superficial part The superficial part of the cardiac plexus lies beneath the aortic arch, in front of the right pulmonary artery. It is formed by the superior cervical cardiac branch of the left sympathetic trunk and the inferior cardiac branch of the left vagus nerve. A small ganglion, the ''cardiac ganglion of Wrisberg'', is occasionally found connected with these nerves at their point of junction. This ganglion, when present, is situate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gray Ramus Communicans
Each spinal nerve receives a branch called a gray ramus communicans (: rami communicantes) from the adjacent paravertebral ganglion of the sympathetic trunk. The gray rami communicantes contain postganglionic nerve fibers of the sympathetic nervous system and are composed of largely unmyelinated neurons. This is in contrast to the white rami communicantes, in which heavily myelinated neurons give the rami their white appearance. Function Preganglionic sympathetic fibers from the intermediolateral nucleus in the lateral grey column of the spinal cord are carried in the white ramus communicans to the paravertebral ganglia of the sympathetic trunk. Once the preganglionic nerve has traversed a white ramus communicans, it can do one of three things. * The preganglionic neuron can synapse with a postganglionic sympathetic neuron in the sympathetic paravertebral ganglion at that level. From here, the postganglionic sympathetic neuron can travel back out the grey ramus communicans of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Ramus Communicans
The white ramus communicans (: rami communicantes) from Latin ramus (branch) and communicans (communicating) is the preganglionic sympathetic outflow nerve tract from the spinal cord. Each of the thoracic, and the first and second lumbar nerves contribute a white ramus communicans to the adjoining sympathetic ganglion, unlike the gray rami which are located at each spinal level. White rami communicantes contain both myelinated and unmyelinated preganglionic sympathetic fibers, ( GVE and GVA). The white ramus appears white because there are more myelinated than unmyelinated fibers unlike the gray rami. Structure The white rami communicantes are the preganglionic sympathetic outflow from the spinal cord. The cell bodies for the preganglionic sympathetic myelinated fibers in the white rami communicantes lie in the ipsilateral (same sided) intermediolateral cell column in the spinal cord which extends from T1-L2. These rami also contain general visceral afferent fibers (sensory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sacral Ganglia
The sacral ganglia are paravertebral ganglia of the sympathetic trunk.:39 As the sympathetic trunk heads inferiorly down the sacrum, it turns medially. There are generally four or five sacral ganglia. In addition to gray rami communicantes, the ganglia send off sacral splanchnic nerves to join the inferior hypogastric plexus. Near the coccyx, the right and left sympathetic trunks join to form the ganglion impar. The sacral ganglia innervate blood vessels and sweat glands of the lower limbs. Clinical significance Recurrences of genital herpes are caused by herpes simplex virus Herpes simplex virus 1 and 2 (HSV-1 and HSV-2) are two members of the Herpesviridae#Human herpesvirus types, human ''Herpesviridae'' family, a set of viruses that produce Viral disease, viral infections in the majority of humans. Both HSV-1 a ... (either HSV-1 or HSV-2) which lies dormant in the sacral ganglia between bouts of active infection. Either primary infection or reactivation may be silent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
