Infobox Anatomy Name PAGENAME Latin hilum nodi lymphoidei GraySubject GrayPage Image Schematic of lymph node showing lymph sinuses.png Caption Schematic of lymph node showing lymph sinuses Image2 Illu lymph node structure.png Caption2 A lymph node showing Afferent lymph vessel afferent and Efferent lymph vessel efferent lymphatic vessel s Precursor System Artery Vein Nerve Lymph MeshName MeshNumber The hilum of lymph node is the concave portion of the lymph node where the efferent vessels exit. ref name urlDefinition hilum of lymph node from Online Medical Dictionary cite web url http cancerweb.ncl.ac.uk cgi bin omd?hilum of lymph node title Definition hilum of lymph node from Online Medical Dictionary format work accessdate 2008 10 19 ref See also Hilum anatomy References Reflist External links BUHistology 07101loa lymphatic stub Category Lymphatic organ anatomy Lymphatic system ... more details
Infobox Anatomy Name PAGENAME Latin cortex nodi lymphoidei GraySubject GrayPage Image Illu lymph node structure.png Caption A lymph node showing Afferent lymph vessel afferent and Efferent lymph vessel efferent lymphatic vessel s Image2 Caption2 Precursor System Artery Vein Nerve Lymph MeshName MeshNumber The cortex of lymph node is the peripheral portion of the lymph node , underneath the capsule. ref name urlDefinition cortex of lymph node from Online Medical Dictionary cite web url http cancerweb.ncl.ac.uk cgi bin omd?cortex of lymph node title Definition cortex of lymph node from Online Medical Dictionary format work accessdate 2008 10 19 ref See also Cortex anatomy cortex References Reflist External links BUHistology 07101loa Lymphatic system Category Lymphatic organ anatomy lymphatic stub ... more details
Infobox Nerve Name PAGENAME Latin neurofibrae efferentes GraySubject GrayPage Image Caption Image2 Caption2 Precursor System Artery Vein Nerve Lymph MeshName MeshNumber Code TerminologiaHistologica 2 00 06.1.00016 In the nervous system , efferent nerves , otherwise known as motoneuron motor or effector neurons , carry action potential nerve impulses away from the central nervous system to effectors such as muscle s or gland s and also the ciliated cells of the inner ear . The term can also be used to describe relative connections between nervous structures for example, a neuron s efferent synapse provides input to another neuron, and not vice versa . The opposite activity of direction or flow is afferent nerve afferent . The motor nerve s are efferent nerves involved in muscular control. The cell biology cell soma biology body of the efferent neuron is connected to a single, long axon and several shorter dendrite s projecting out of the cell body itself. This axon then forms a neuromuscular junction with the effectors. The cell body of the motor neuron is satellite shaped. The motor neuron is present in the grey matter of the spinal cord and medulla oblongata , and forms an electrochemical pathway to the wikt effector effector organ or muscle. Besides motor nerves, there are efferent sensory nerves that often serve to adjust the sensitivity of the signal relayed by the afferent sensory nerve. Etymology and mnemonics Both afferent and efferent come from French language French , evolved from Latin the basis of many terms in medicine and biology for the terms, respectively, ad ferens Latin verb ferre carry , meaning carrying into , and ex ferens , meaning carrying away . Ad and ex give an easy mnemonic device for remembering the relationship between afferent and efferent a fferent connection a rrives and an e fferent connection e xits . ref MedicalMnemonics 3502 3463 367 115 ref See also Nerve fiber Afferent nerve fiber Motor nerve Interneuron General somatic efferent ... more details
. When the test is performed in an eye with an afferent pupillary defect, light directed in the affected ... the afferent defect , while light in the unaffected eye will cause a normal constriction of both pupils due to an intact afferent path, and an intact consensual pupillary reflex . Thus, light shone ... more details
fibers. Innervation As intrafusal muscle fibers, nuclear chain fibers both send afferent innvervation and receive efferent innervation. The afferent innervation is via Group II and Ia neurons. These project ... more details
distinguish Magnocellular cell Magnocellular neurosecretory cells are large cell biology cell s within the supraoptic nucleus and paraventricular nucleus of the hypothalamus . They are also found in smaller numbers in accessory cell groups between these two nuclei, the largest one being the nucleus circularis . There are two types of magnocellular neurosecretory cells, oxytocin producing cells and vasopressin producing cells, but a small number can produce both hormone s. These cells are Neuroendocrinology neuroendocrine neuron s, are electrically excitable, and generate action potential s in response to afferent stimulation. Magnocellular neurosecretory cells in the rat where these neurons have been most extensively studied in general have a single long varicose axon, which projects to the posterior pituitary . Each axon gives rise to about 10,000 neurosecretory terminals and many axon swellings that store very large numbers of hormone containing vesicles. These vesicles are released from the axon swellings and nerve terminals by exocytosis in response to calcium entry through voltage gated channels, which occurs when action potential s are propagated down the axons. The cells typically have two or three long dendrites, which also contain large dilations, and which also contain a very high density of hormone containing vesicles. Oxytocin and vasopressin can, thus, be released within the brain from these dendrites, as well as into the blood from the terminals in the posterior pituitary gland. However, the release of oxytocin and vasopressin from dendrites is not consistently accompanied by peripheral secretion, as dendritic release is regulated differently. Dendritic release can be triggered by depolarisation, but can also be triggered by the mobilisation of intracellular calcium stores. The dendrites receive most of the synaptic inputs from afferent neurons that regulate the magnocellular neurons typically a magnocellular neuron receives about 10,000 synapses from ... more details
Infobox Anatomy Name White ramus communicans Latin ramus communicans albus nervi spinalis GraySubject 208 GrayPage 920 Image Gray799.svg Caption Scheme showing structure of a typical spinal nerve . 1. Somatic efferent. 2. Somatic afferent. 3,4,5. Sympathetic efferent. 6,7. Sympathetic afferent. Image2 Gray819.png Caption2 Diagram of the course and branches of a typical intercostal nerve. Rami communicantes labeled at center. System MeshName MeshNumber DorlandsPre r 02 DorlandsSuf 12689486 The thoracic, and the first and second lumbar nerves each contribute a branch, white ramus communicans to the adjoining sympathetic ganglion . They contain myelinated preganglionic Sympathetic nervous system sympathetic fibers General visceral efferent fibers GVE and General visceral afferent fibers GVA . Unlike the gray rami , white rami communicantes do not extend below L2 or above T1. ref cite web url http anatomy.med.umich.edu gastrointestinal system kidney ans.html title Dissector Answers Kidney & Retroperitoneum accessdate 2007 11 13 work ref Additional images gallery Image Gray824.png Deep and superficial dissection of the lumbar plexus. Image Gray846.png Thoracic portion of the sympathetic trunk. gallery See also Gray ramus communicans References reflist External links eMedicineDictionary white rami communicantes UMichAtlas n3a6p1 Autonomic Connections of the Spinal Cord http 137.222.110.150 calnet ANS page2.htm Overview and diagram Gray s Autonomic Nervous tissue Category Nerves of the torso neuroscience stub ca Branca comunicant blanca tl White ramus communicans ... more details
Image Renal arterial hyalinosis pas very high mag.jpg thumb Micrograph showing hyaline arteriolosclerosis in the kidney . PAS stain . Hyaline arteriolosclerosis , also arterial hyalinosis and arteriolar hyalinosis , refers to thickening of the walls of arterioles by the deposition of homogeneous pink hyaline material. ref name pmid2420184 cite journal author Gamble CN title The pathogenesis of hyaline arteriolosclerosis journal Am. J. Pathol. volume 122 issue 3 pages 410 20 year 1986 month March pmid 2420184 pmc 1888226 doi url ref It is a type of arteriolosclerosis which refers to hardening of arteriole arteriolar wall. Associations It is associated with aging, hypertension , diabetes mellitus ref name Robbins2007 cite book author Robbins, Stanley L. Kumar, Vinay authorlink editor others title Robbins basic pathology edition language publisher Saunders Elsevier location year 2007 origyear pages 356 quote isbn 0 8089 2366 8 oclc doi url accessdate ref and may be seen in response to certain drugs calcineurin inhibitor s . It is often seen in the context of kidney pathology. In hypertension only the afferent arteriole is affected, while in diabetes mellitus, both the afferent arteriole afferent and efferent arteriole are affected. Etiology Lesions reflect leakage of Blood plasma plasma components across vascular endothelium and excessive extracellular matrix production by smooth muscle cells , usually secondary to hypertension. Hyaline arteriolosclerosis is a major morphologic characteristic of benign nephrosclerosis , in which the arteriolar narrowing causes diffuse impairment of renal blood supply , with loss of nephrons . ref name Robbins2007 The narrowing of the lumen can decrease renal blood flow and hence glomerular filtration rate leading to increased renin secretion and a perpetuating cycle with increasing blood pressure and decreasing kidney function. References reflist Vascular diseases Category Vascular diseases ... more details
, it triggers dilation of the renal afferent arteriole, decreasing afferent arteriole resistance ... lining the afferent arterioles to release renin into the bloodstream. The juxtaglomerular cells ... rate GFR fairly steady in response to varying artery pressure, due to dilation of the afferent ... more details
crude touch, temperature and pain Inferior olivary nucleus afferent fibres to cerebellum References ... Primary terminal nuclei of the afferent sensory cranial nerves schematically represented lateral ... more details
Infobox Nerve Name PAGENAME Latin ganglion vestibulare GraySubject 203 GrayPage 906 Image Caption Image2 Caption2 Innervates BranchFrom BranchTo MeshName MeshNumber DorlandsPre g 02 DorlandsSuf 12385160 The vestibular nerve ganglion also called Scarpa s ganglion is the ganglion of the vestibular nerve . It contains the cell bodies of the bipolar primary afferent nerve afferent neurons whose peripheral processes form synaptic contact with hair cells of the vestibular system vestibular sensory end organs. It is named for Antonio Scarpa . ref WhoNamedIt synd 2928 ref ref A. Scarpa. Anatomicarum annotationum. 2 volumes, Modena and Pavia, 1779, 1785. 2nd edition, Milano, 1792. ref At birth, it is already close to its final size. ref name pmid1518353 cite journal author Sato H, Sando I, Takahashi H title Three dimensional anatomy of human Scarpa s ganglion journal Laryngoscope volume 102 issue 9 pages 1056 63 year 1992 month September pmid 1518353 doi 10.1288 00005537 199209000 00018 ref References reflist External links eMedicineDictionary vestibular ganglion http www.vestib.org chap4anatphysio imagesch4 innerv.gif Diagram in French http oto.wustl.edu bbears scarpa.htm Histology at wustl.edu Neuroscience stub Cranial nerves Auditory and vestibular pathways Category Nervous system Category Vestibular system sr ... more details
The swinging flashlight test is used to help a practitioner decide whether reduced vision is due to ocular disease. Process For an adequate test, vision must not be entirely lost. In dim room light, the examiner notes the size of the pupils. The patient is asked to gaze into the distance, and the examiner swings the beam of a Flashlight penlight back and forth from one pupil to the other, and observes the size of pupils and reaction in the eye that is lit. Interpretation Normally, each illuminated eye looks or promptly becomes constricted. The opposite eye also constricts consensually. When ocular disease, such as cataract , impairs vision, the pupils respond normally. When the optic nerve is damaged, the sensory afferent stimulus sent to the midbrain is reduced. The pupil, responding less vigorously, dilates from its prior constricted state. This response is an afferent pupillary defect Marcus Gunn Pupil . References Bickley L.S. 2003. Bates guide to physical examination and history taking. 8th ed. Lippincott Williams and Wilkins, New York. pp. 169. See also Eye examination External links http library.med.utah.edu neurologicexam html cranialnerve normal.html 05 Physical exam Category Medical signs de Swinging Flashlight Test ... more details
Infobox Nerve Name PAGENAME Latin ganglia trunci sympathici GraySubject 214 GrayPage 976 Image Gray847.png Caption Abdominal portion of the sympathetic trunk , with the celiac plexus and hypogastric plexus . Sympathetic trunk labeled at center left. Image2 Gray799.svg Caption2 Scheme showing structure of a typical spinal nerve . 1. Somatic efferent. 2. Somatic afferent. 3,4,5. Sympathetic efferent. 6,7. Sympathetic afferent. Innervates BranchFrom BranchTo MeshName MeshNumber DorlandsPre g 02 DorlandsSuf 12385109 Along the length of the sympathetic trunk are ganglia known as ganglia of sympathetic trunk or paravertebral ganglia . The ganglia are distinguished as cervical ganglia cervical , thoracic ganglia thoracic , lumbar ganglia lumbar , and sacral ganglia sacral and, except in the neck, they closely correspond in number to the vertebrae . Arrangement Only the cervical ganglia have specific names. They are arranged thus cervical ganglia 3 ganglia thoracic ganglia 12 ganglia lumbar ganglia 4 ganglia sacral ganglia 4 ganglia Additional images gallery Image Gray530.png The thoracic aorta, viewed from the left side. gallery External links eMedicineDictionary ganglia of sympathetic trunk UMichAtlas n3a6p1 Autonomic Connections of the Spinal Cord Autonomic Gray s Category Nervous system circulatory stub ca Gangli paravertebral ... more details
Infobox Brain Name Solitary tract Latin tractus solitarius medullae oblongatae GraySubject 187 GrayPage 785 Image Gray695.png Caption Transverse section of medulla oblongata below the middle of the olive. Fasciculus solitarius labeled at upper right. Image2 Gray700.png Caption2 The formatio reticularis of the medulla oblongata, shown by a transverse section passing through the middle of the olive. 15 is fasciculus solitarius IsPartOf Components Artery Vein Acronym BrainInfoType hier BrainInfoNumber 782 MeshName MeshNumber NeuroLex Solitary tract NeuroLexID birnlex 1483 DorlandsPre t 15 DorlandsSuf 12817166 The solitary tract lang la tractus solitarius is a compact fiber bundle that extends longitudinally through the posterolateral region of the Medulla oblongata medulla . The solitary tract is surrounded by the nucleus of the solitary tract , and descends to the upper cervical segments of the spinal cord . Composition The solitary tract is made up of primary sensory fibers and descending fibers of the Vagus nerve vagus , glossopharyngeal nerve glossopharyngeal , and facial nerve s. Function The solitary tract conveys afferent information from stretch receptors and chemoreceptors in the walls of the cardiovascular, respiratory, and intestinal tracts. Afferent fibers from cranial nerves facial nerve 7 , glossopharyngeal nerve 9 and vagus nerve 10 convey taste special visceral afferent SVA in its rostral portion, and general visceral sense general visceral afferent fibers GVA in its caudal part. Taste bud s in the mucosa of the tongue can also generate impulses in the Anatomical terms of location Directional terms rostral regions of the solitary tract. The efferent fibers are distributed to the solitary tract nucleus. Synonyms There are numerous synonyms for the solitary tract round fasciculus Latin fasciculus rotundus solitary fasciculus Latin fasciculus solitarius solitary bundle Latin funiculus solitarius Gierke respiratory bundle Krause respiratory bundle See also ... more details
Infobox Nerve Name PAGENAME Latin nervi splanchnici lumbales GraySubject GrayPage Image Caption Image2 Caption2 Innervates BranchFrom BranchTo MeshName MeshNumber DorlandsPre n 05 DorlandsSuf 12566685 The lumbar splanchnic nerves are splanchnic nerves that arise from the lumbar part of the sympathetic trunk and travel to an adjacent plexus near the aorta . They are originated from L1 and L2. These nerves contain preganglionic sympathetic and visceral afferent fibers. The site of synapse is found in the inferior mesenteric ganglion and the postsynaptic fibers innervate the smooth muscle and glands of the pelvic viscera and hindgut . External links eMedicineDictionary lumbar splanchnic nerves DartmouthHumanAnatomy figures chapter 32 32 6.HTM Autonomic neuroanatomy stub Category Nerves ... more details
Stretch receptors are mechanoreceptors responsive to distention of various organs and muscles, and are neurologically linked to the Medulla oblongata medulla in the brain stem via afferent nerve fibers. Examples include stretch receptors in the arm and leg muscles and tendons, in the heart, in the colon wall, and in the lungs. Stretch receptors are also found around the carotid artery, where they monitor blood pressure and stimulate the release of vasopressin ADH from posterior pituitary gland. Types include Golgi organ Muscle spindle Pulmonary stretch receptors Chordotonal organ , in insects External links eMedicineDictionary stretch receptors DorlandsDict seven 000091067 Stretch receptor MeshName Stretch receptor Somatosensory system disambig ... more details
Infobox Brain Name PAGENAME Latin nucleus reticularis ventralis GraySubject GrayPage Image Caption Image2 Caption2 IsPartOf Components Artery Vein BrainInfoType hier BrainInfoNumber 730 MeshName MeshNumber DorlandsPre DorlandsSuf The ventral reticular nucleus is a continuation of the parvocellular nucleus in the brainstem . The ventral reticular nucleus has been shown to receive afferent projections from the dentate gyrus in rabbits ref Tang, ZW et al. The fiber projections from the dentate nucleus to the reticular formation of the brain stem in the rabbit. Anatomy and Embryology Berlin . 1987 175 4 517 20. ref . The rostral portion of the ventral reticular nucleus has been shown to mediate Inhalation inspiration along with a portion of the lateral reticular nucleus . References references Category Medulla oblongata neuroscience stub Reticular formation Rhombencephalon ... more details
Infobox Lymph Name PAGENAME Latin nodi lymphoidei parotidei superficiales GraySubject GrayPage Image illu lymph chain01.jpg Caption 3. Superficial Parotid Image2 Caption2 DrainsFrom Source DrainsTo MeshName MeshNumber DorlandsPre n 09 DorlandsSuf 12576913 The superficial parotid lymph nodes are a group of lymph nodes anterior to the ear. Their afferent vessels drain the root of the Human nose nose , the eyelids , the frontotemporal region, the external acoustic meatus and the tympanic cavity , possibly also the posterior parts of the palate and the floor of the nasal cavity . The efferents of these glands pass to the superior deep cervical glands. Gray s lymphatic stub Lymphatics of head and neck Category Lymphatics of the head and neck ... more details
Lymph trunk is a lymph vessel that carries lymph, and is formed by confluence of many efferent lymph vessel s. It in turn drains into one of the two lymph ducts right lymph duct and the thoracic duct . When an efferent lymph vessel leaves a lymph node, it may carry lymph to another lymph node by becoming its afferent lymph vessel or unite with other efferent vessels to become a lymph trunk. The lymph trunks drain into the lymph ducts, which in turn return lymph to the blood by emptying into the respective subclavian vein s. There are four pairs and an unpaired lymph trunks Jugular lymph trunk s Subclavian lymph trunk s Bronchomediastinal lymph trunk s Lumbar lymph trunk s Intestinal lymph trunk &mdash unpaired Lymphatic flow DEFAULTSORT Lymph Trunk Category Lymphatic system ... more details
Nofootnotes article date July 2009 Polkissen cells are located between the afferent and efferent arterioles at the vascular pole of the glomerulus , adjacent to the macula densa . Their function is to measure the blood flow to the nephron s, and release renin into the blood stream if the blood pressure is low. External links cite journal author Baumbach L, Sk tt title Isolated glomeruli in vitro an approach to the macula densa mediated renin release journal Kidney International volume 12 issue pages S73 7 year 1982 month August pmid 6752542 Category Kidney anatomy ... more details
In physiology high pressure receptor zones are the places you find baroreceptor s in the aortic arch and carotid sinus . They are only sensitive above 60 mmHg blood pressure . When these receptors are active they elicit a depressor response which decreases the heart rate and gives a general vasodilation . An increase in arterial blood pressure reflexly elicits an increase in vagal neuronal activity to the heart i.e. the resulting decreased heart rate . The afferent nerves from the baroreceptors are called buffer nerves. See also Low pressure receptor zones . bainbridge reflex References Reflist Principles of medical physiology by A Fonyo page 577 circulatory stub neuroanatomy stub Category Sensory receptors ... more details
orphan date January 2012 Charles Scott Sherrington originally introduced the term to neurophysiology to encompassed just viscera l Sense sensations , but the term is later used to include the physiological condition of the entire body and the ability of visceral afferent information to reach awareness and affect behaviour, either directly or indirectly. ref http brain.oxfordjournals.org content 126 6 1505.full ref In nondualism nondual philosophy , Franklin Merrell Wolff used introception to designate a mode of knowledge becoming available in transcendent state of consciousness through identification with that which is known. ref http www.cejournal.org GRD Wolff.htm ref See also Proprioception Perception Phenomenon References reflist Category Neurophysiology Category Pluralism ... more details
Infobox anatomy Name Thoracic lymph nodes Latin nodi lymphoidei thoracis GraySubject 181 GrayPage 715 Image Gray621.png Caption Deep lymph nodes and vessels of the thorax and abdomen diagrammatic . Afferent vessels are represented by continuous lines, and efferent and internodular vessels by dotted lines. Image2 Gray622.png Caption2 The tracheobronchial lymph glands. Precursor System Artery Vein Nerve Lymph MeshName MeshNumber The lymph glands of the thorax may be divided into wikt parietal parietal and visceral the former being situated in the thoracic wall , the latter in relation to the viscera . Gray s Thoracic lymph nodes Category Lymphatics of the torso anatomy stub ... more details
an afferent arteriole of the renal circulation . Unlike most other capillary beds, the glomerulus ... GFR . Afferent circulation The afferent arteriole that supplies the capillaries of a glomerulus branches ... filtration rate, can be influenced by constriction or relaxation of the afferent arteriole ... narrowed afferent arterioles contributed to the development of increased blood pressure. ref cite journal last1 Norrelund first1 H last2 Christensen first2 KL year 1994 title Early narrowed afferent ... also impact glomerular filtration rate by modulating afferent arteriole diameter. Layers If a substance ... into an interlobular vein . Juxtaglomerular cells The walls of the afferent arteriole contain specialized ... more details
Infobox Nerve Name Spinal nerve Latin nervi spinales GraySubject 208 GrayPage 916 Image spinal nerve.svg Caption The formation of the spinal nerve from the dorsal and ventral roots Image2 Gray799.svg Caption2 Scheme showing structure of a typical spinal nerve. BR 1. General somatic efferent fibers Somatic efferent . BR 2. General somatic afferent fibers Somatic afferent . BR 3,4,5. General visceral efferent fibers Sympathetic efferent . BR 6,7. General visceral afferent fibers Sympathetic afferent . Innervates BranchFrom BranchTo MeshName Spinal nerves MeshNumber A08.800.800.720 Code TA A14.2.00.027 The term spinal nerve generally refers to a mixed spinal nerve , which carries motor, sensory, and autonomic signals between the spinal cord and the body. Humans have 31 left right pairs of spinal nerves, each roughly corresponding to a segment of the vertebral column 8 cervical spinal nerve pairs C1 C8 , 12 thoracic pairs T1 T12 , 5 lumbar pairs L1 L5 , 5 sacral pairs S1 S5 , and 1 coccygeal pair. The spinal nerves are part of the peripheral nervous system PNS . Anatomy Each spinal nerve is formed by the combination of nerve fibers from the Posterior root of spinal nerve dorsal and Anterior root of spinal nerve ventral roots of the spinal cord . The dorsal roots carry afferent nerve afferent sensory neuron sensory axons , while the ventral roots carry efferent nerve efferent motoneuron motor axons . The spinal nerve emerges from the spinal column through an opening intervertebral foramen between adjacent vertebrae. This is true for all spinal nerves except for the first spinal nerve pair, which emerges between the occipital bone and the Atlas anatomy atlas the first vertebra . Thus the cervical nerves are numbered by the vertebra below, except C8, which exists below C7 and above T1. The thoracic, lumbar, and sacral nerves are then numbered by the vertebra above. In the case of a lumbarized S1 vertebra aka L6 or a sacralized L5 vertebra, the nerves are typically still co ... more details
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