Trigeminal Nucleus, Spinal
Trigeminal Nuclei
Trigeminal Caudal Nucleus
Trigeminal Nerve
Cell Nucleus
Facial Pain
Vibrissae
Dihydroergotamine
Sumatriptan
Trigeminal Ganglion
Brain Stem
Afferent Pathways
Meninges
Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate
Pons
Cochlear Nucleus
Central Nervous System Sensitization
Rats, Sprague-Dawley
Nociceptors
Neurons
Proto-Oncogene Proteins c-fos
Medulla Oblongata
Dura Mater
Dental Pulp
Substantia Gelatinosa
Vesicular Glutamate Transport Protein 2
Receptors, Calcitonin Gene-Related Peptide
Cortical Spreading Depression
Cats
Masticatory Muscles
Nerve Fibers
Mechanoreceptors
Mesencephalon
Calcitonin Gene-Related Peptide
Migraine Disorders
Somatosensory Cortex
Evoked Potentials
Nucleus Accumbens
Thalamus
Temporomandibular Joint
Action Potentials
Thalamic Nuclei
Solitary Nucleus
Immunohistochemistry
Serotonin Receptor Agonists
Neural Inhibition
Spinal Cord
Rats, Wistar
Posterior Horn Cells
Raphe Nuclei
Cerebellar Nuclei
Brain
Septal Nuclei
Active Transport, Cell Nucleus
Arcuate Nucleus
Caudate Nucleus
Pain
Electrophysiology
Brain Mapping
Suprachiasmatic Nucleus
Red Nucleus
C-fiber depletion alters response properties of neurons in trigeminal nucleus principalis. (1/203)
The effects of C-fiber depletion induced by neonatal capsaicin treatment on the functional properties of vibrissa-sensitive low-threshold mechanoreceptive (LTM) neurons in the rat trigeminal nucleus principalis were examined in adult rats. Neonatal rats were injected either with capsaicin or its vehicle within 48 h of birth. The depletion of unmyelinated afferents was confirmed by the significant decrease in plasma extravasation of Evan's blue dye induced in the hindlimb skin of capsaicin-treated rats by cutaneous application of mustard oil and by the significant decrease of unmyelinated fibers in both the sciatic and infraorbital nerves. The mechanoreceptive field (RF) and response properties of 31 vibrissa-sensitive neurons in capsaicin-treated rats were compared with those of 32 vibrissa-sensitive neurons in control (untreated or vehicle-treated) rats. The use of electronically controlled mechanical stimuli allowed quantitative analysis of response properties of vibrissa-sensitive neurons; these included the number of center- and surround-RF vibrissae within the RF (i.e., those vibrissae which when stimulated elicited >/=1 and <1 action potential per stimulus, respectively), the response magnitude and latency, and the selectivity of responses to stimulation of vibrissae in different directions with emphasis on combining both the response magnitude and direction of vibrissal deflection in a vector analysis. Neonatal capsaicin treatment was associated with significant increases in the total number of vibrissae, in the number of center-RF vibrissae per neuronal RF, and in the percentage of vibrissa-sensitive neurons that also responded to stimulation of other types of orofacial tissues. Compared with control rats, capsaicin-treated rats showed significant increases in the response magnitude to stimulation of surround-RF vibrissae as well as in response latency variability to stimulation of both center- and surround-RF vibrissae. C-fiber depletion also significantly altered the directional selectivity of responses to stimulation of vibrissae. For neurons with multiple center-RF vibrissae, the proportion of center-RF vibrissae with net vector responses oriented toward the same quadrant was significantly less in capsaicin-treated compared with control rats. These changes in the functional properties of principalis vibrissa-sensitive neurons associated with marked depletion of C-fiber afferents are consistent with similarly induced alterations in LTM neurons studied at other levels of the rodent somatosensory system, and indeed may contribute to alterations previously described in the somatosensory cortex of adult rodents. Furthermore, these results provide additional support to the view that C fibers may have an important role in shaping the functional properties of LTM neurons in central somatosensory pathways. (+info)Outward currents influencing bursting dynamics in guinea pig trigeminal motoneurons. (2/203)
To initiate and maintain bursts (and plateau potentials) in the presence of serotonin, guinea pig trigeminal motoneurons utilize L-type Ca2+ and persistent Na+ inward currents. However, the intrinsic currents that contribute to burst termination and determine the duration of the interburst interval are unknown. Therefore we investigated the roles of outward currents, whose slow activation is coupled to cytosolic cation (Ca2+ and Na+) accumulation. First we examined a Ca2+-dependent K+ current (IK-Ca) with apamin and Ba2+-substituted, low-Ca2+ solution. Blockade of IK-Ca lengthened burst duration and cycle time but did not abolish bursting. Next we studied the Na+/K+-ATPase pump current (Ip) with cardiac glycosides. In the presence of apamin or low-Ca2+/Ba2+ solution, blocking Ip (with ouabain or strophanthidin) decreased both burst duration and cycle time and ultimately transformed bursting into tonic spiking. We conclude that IK-Ca and Ip contribute to burst termination in trigeminal motoneurons. These currents influence temporal bursting properties such as burst duration and cycle time and may help determine the phasic activity of motoneurons during rhythmic oral-motor behaviors. (+info)Distribution of the low-affinity neurotrophin receptor (p75) in the developing trigeminal brainstem complex in the rat. (3/203)
The low-affinity neurotrophin receptor (p75) binds all members of the neurotrophin family. In the rat, during the first week postpartum, dense p75-immunoreactivity (IR) is present throughout all components of the trigeminal brainstem complex (TBC), largely associated with primary sensory afferents. Within subnucleus caudalis (SpC) of the TBC, intense p75-IR is present in all laminae at birth. During the second and third postnatal weeks, p75-IR in SpC gradually fades within the deeper laminae, becoming generally restricted in the adult to laminae I and II. Similar declines in p75-IR intensity occur in the subnucleus oralis (SpO); in the SpO in the adult, p75-IR is confined to the dorsalmost portion of SpO. In subnucleus interpolaris, an emerging, vibrissa-related pattern of p75-IR is detectable on PD0 (first 24 hr postpartum), which becomes fully differentiated during PD4-PD7. However, this pattern gradually disappears during the third postnatal week. Ventrally in the nucleus principalis (PrV), a pattern of p75-IR that mirrors the topographical arrangement of the vibrissae is detectable by PD0-PD1, is fully differentiated by the end of the first postnatal week, and persists into adulthood. Perinatal unilateral sectioning of the infraorbital nerve on PD0-PD1, but not as late as PD4, disrupts p75-IR patterning in the adult PrV. Although p75 appears to be associated with primary afferent pattern formation, to determine whether it is essential, we examined mutant mice unable to form functional p75. In the TBC of these knockout mice, examined as adults, patterns of cytochrome oxidase staining (which parallel those of p75-IR) appeared to be normal. In summary, during early development, p75 is widely expressed in the TBC during periods of active synaptogenesis and pattern formation, whereas in the adult, its expression is restricted to association with populations of primary sensory afferents. However, the absence of functional p75 in genetically altered mice does not appear to prevent primary afferent pattern formation. (+info)Dural vasodilation causes a sensitization of rat caudal trigeminal neurones in vivo that is blocked by a 5-HT1B/1D agonist. (4/203)
1. Migraine headache pain is thought to result from an abnormal distention of intracranial, extracerebral blood vessels and the consequent activation of the trigeminal nervous system. Migraine is also often accompanied by extracranial sensory disturbances from facial tissues. These experiments investigate whether meningeal dilation produces central sensitization of neurones that receive convergent input from the face. 2. Single unit extracellular activity was recorded from the trigeminal nucleus caudalis of anaesthetized rats in response to either noxious stimulation of the dura mater, innocuous stimulation of the vibrissae or to a transient dilation of the meningeal vascular bed. 3. Rat alpha-CGRP (calcitonin gene-related peptide; 1 microg kg(-1), i.v.) caused a dilation of the middle meningeal artery and facilitated vibrissal responses by 36+/-7%. 4. The 5-HT1B/1D agonist, L-741,604 (3 mg kg(-1), i.v.), inhibited responses to noxious stimulation of the dura mater (16+/-7% of control) and, in a separate group of animals, blocked the CGRP-evoked facilitation of vibrissal responses. 5. L-741,604 (3 mg kg(-1), i.v.) also inhibited responses to innocuous stimulation of the vibrissa (14+/-10% of control) with neurones that received convergent input from the face and from the dura mater, but not with cells that received input only from the face (70+/-12% of control). 6. These data show that dilation of meningeal blood vessels causes a sensitization of central trigeminal neurones and a facilitation of facial sensory processing which was blocked by activation of pre-synaptic 5-HT1B/1D receptors. 7. Sustained dural blood vessel dilation during migraine may cause a sensitization of trigeminal neurones. This may underlie some of the symptoms of migraine, such as the headache pain and the extracranial allodynia. Inhibition of this central sensitization may therefore offer a novel strategy for the development of acute and/or prophylactic anti-migraine therapies. (+info)Single- and multi-whisker channels in the ascending projections from the principal trigeminal nucleus in the rat. (5/203)
This study investigated the relationship between axonal projections and receptive field properties of whisker-sensitive cells in the principal trigeminal sensory nucleus of the rat. The labeling of small groups of trigeminothalamic axons with biotinylated dextran amine disclosed two broad classes of axons; a majority of fibers (68%; n = 107) project to a single barreloid of the ventral posteromedial nucleus, and the remaining group includes axons that innervate both the posterior group of the thalamus and the tectum. Additional terminal sites for axons of this latter group may include the pretectum, the zona incerta, the medial part of the medial geniculate nucleus, and the ventral posteromedial nucleus. Corresponding to these two classes of fibers, 67% of the cells in the principal trigeminal nucleus (n = 313) have single-whisker receptive fields, whereas the rest of the population have receptive fields composed of multiple whiskers. The tonic or phasic properties of the responses apparently bear no relation to the axonal projection patterns. Solid retrograde labeling of cells that project to the ventral posteromedial nucleus and intracellular staining revealed that single-whisker cells have small somata and narrow, barrelette-bounded dendritic trees. In contrast, multi-whisker neurons have large multipolar somata, expansive dendritic trees, and many respond antidromically to stimulation of the superior colliculus. Together, these results provide evidence for two main channels of vibrissal information: a single-whisker channel that links trigeminal barrelettes to their corresponding barreloids, and a multi-whisker channel that distributes principally in the posterior group and tectum. (+info)Disrupted cortical map and absence of cortical barrels in growth-associated protein (GAP)-43 knockout mice. (6/203)
There is strong evidence that growth-associated protein (GAP-43), a protein found only in the nervous system, regulates the response of neurons to axonal guidance signals. However, its role in complex spatial patterning in cerebral cortex has not been explored. We show that mice lacking GAP-43 expression (-/-) fail to establish the ordered whisker representation (barrel array) normally found in layer IV of rodent primary somatosensory cortex. Thalamocortical afferents to -/- cortex form irregular patches in layer IV within a poorly defined cortical field, which varies between hemispheres, rather than the stereotypic, whisker-specific, segregated map seen in normal animals. Furthermore, many thalamocortical afferents project abnormally to widely separated cortical targets. Taken together, our findings indicate a loss of identifiable whisker territories in the GAP-43 -/- mouse cortex. Here, we present a disrupted somatotopic map phenotype in cortex, in clear contrast to the blurring of boundaries within an ordered whisker map in other barrelless mutants. Our results indicate that GAP-43 expression is critical for the normal establishment of ordered topography in barrel cortex. (+info)Serotonergic modulation of the hyperpolarizing spike afterpotential in rat jaw-closing motoneurons by PKA and PKC. (7/203)
Intracellular recordings were obtained from rat jaw-closing motoneurons (JCMNs) in slice preparations to investigate the effects of serotonin (5-HT) on the postspike medium-duration afterhyperpolarization (mAHP) and an involvement of protein kinases in the effects. Application of 50 microM 5-HT caused membrane depolarization and increased input resistance in the most cells without affecting the mAHP, whereas not only membrane depolarization and an increase in input resistance, but also the suppression of the mAHP amplitude was induced by higher dose of 5-HT (100 or 200 microM). On the other hand, when the mAHP amplitude was increased by raising [Ca(2+)](o) from 2 to 6 mM, 5-HT-induced attenuation of the mAHP amplitude was enhanced, and even 50 microM 5-HT reduced the mAHP amplitude. This 5-HT-induced suppression of the mAHP could be mimicked by application of membrane-permeable cAMP analogue 8-Bromo-cAMP, potentiated by the cAMP-specific phosphodiesterase inhibitor Ro 20-1724 and antagonized by protein kinase A (PKA) inhibitor H89. The enhancement of the mAHP attenuation induced by 50 microM 5-HT under raised [Ca(2+)](o) was blocked by a protein kinase C (PKC) inhibitor chelerythrine, suggesting an involvement of PKC in this enhancement. On the other hand, the attenuation of the mAHP induced by PKC activator phorbol 12-myristate 13-acetate was blocked almost completely by H89, suggesting that the PKC action on the mAHP requires PKA activation. Neither 5-HT(1A) antagonist NAN-190 or 5-HT(4) antagonist SB 203186 blocked 5-HT-induced attenuation of the mAHP. We conclude that 5-HT induces dose-dependent attenuation of the mAHP amplitude through cAMP-dependent activation of PKA and that PKC-dependent PKA activation is also likely to be involved in the enhancement of 5-HT-induced attenuation of the mAHP under raised [Ca(2+)](o). Because the slope of the linear relationship between firing frequency and injected current was increased only when the mAHP amplitude was decreased by 5-HT, it is suggested that the relation between incoming synaptic inputs and firing output in JCMNs varies according to serotonergic effects on JCMNs and calcium-dependent modulation of its effects. (+info)Reciprocal connections between the red nucleus and the trigeminal nuclei: a retrograde and anterograde tracing study. (8/203)
An anterograde biocytin and a retrograde WGA-colloidal gold study in the rat can provide information about reciprocal communication pathways between the red nucleus and the trigeminal sensory complex. No terminals were found within the trigeminal motor nucleus, in contrast with the facial motor nucleus. A dense terminal field was observed in the parvicellular reticular formation ventrally to the trigeminal motor nucleus. The parvicellular area may be important for the control of jaw movements by rubrotrigeminal inputs. On the other hand, the contralateral rostral parvicellular part of the red nucleus receives terminals from the same zone in the rostral part of the trigeminal sensory complex, where retrogradely labelled neurones were found after tracer injections into the red nucleus. Such relationships could be part of a control loop for somatosensory information from the orofacial area. (+info)The spinal trigeminal nucleus is a component of the trigeminal nerve sensory nuclear complex located in the brainstem. It is responsible for receiving and processing pain, temperature, and tactile discrimination sensations from the face and head, particularly from the areas of the face that are more sensitive to pain and temperature (the forehead, eyes, nose, and mouth). The spinal trigeminal nucleus is divided into three subnuclei: pars oralis, pars interpolaris, and pars caudalis. These subnuclei extend from the pons to the upper part of the medulla oblongata.
The trigeminal nuclei are a collection of sensory nerve cell bodies (nuclei) located in the brainstem that receive and process sensory information from the face and head, including pain, temperature, touch, and proprioception. There are four main trigeminal nuclei: the ophthalmic, maxillary, mandibular, and mesencephalic nuclei. Each nucleus is responsible for processing sensory information from specific areas of the face and head. The trigeminal nerve (cranial nerve V) carries these sensory signals to the brainstem, where they synapse with neurons in the trigeminal nuclei before being relayed to higher brain centers for further processing.
The Trigeminal Caudal Nucleus, also known as the nucleus of the spinal trigeminal tract or spinal trigeminal nucleus, is a component of the trigeminal nerve sensory nuclear complex located in the brainstem. It is responsible for receiving and processing pain and temperature information from the face and head, particularly from the areas innervated by the ophthalmic (V1) and maxillary (V2) divisions of the trigeminal nerve. The neurons within this nucleus then project to other brainstem regions and ultimately to the thalamus, which relays this information to the cerebral cortex for conscious perception.
The trigeminal nerve, also known as the fifth cranial nerve or CNV, is a paired nerve that carries both sensory and motor information. It has three major branches: ophthalmic (V1), maxillary (V2), and mandibular (V3). The ophthalmic branch provides sensation to the forehead, eyes, and upper portion of the nose; the maxillary branch supplies sensation to the lower eyelid, cheek, nasal cavity, and upper lip; and the mandibular branch is responsible for sensation in the lower lip, chin, and parts of the oral cavity, as well as motor function to the muscles involved in chewing. The trigeminal nerve plays a crucial role in sensations of touch, pain, temperature, and pressure in the face and mouth, and it also contributes to biting, chewing, and swallowing functions.
The cell nucleus is a membrane-bound organelle found in the eukaryotic cells (cells with a true nucleus). It contains most of the cell's genetic material, organized as DNA molecules in complex with proteins, RNA molecules, and histones to form chromosomes.
The primary function of the cell nucleus is to regulate and control the activities of the cell, including growth, metabolism, protein synthesis, and reproduction. It also plays a crucial role in the process of mitosis (cell division) by separating and protecting the genetic material during this process. The nuclear membrane, or nuclear envelope, surrounding the nucleus is composed of two lipid bilayers with numerous pores that allow for the selective transport of molecules between the nucleoplasm (nucleus interior) and the cytoplasm (cell exterior).
The cell nucleus is a vital structure in eukaryotic cells, and its dysfunction can lead to various diseases, including cancer and genetic disorders.
Facial pain is a condition characterized by discomfort or pain felt in any part of the face. It can result from various causes, including nerve damage or irritation, injuries, infections, dental problems, migraines, or sinus congestion. The pain can range from mild to severe and may be sharp, dull, constant, or intermittent. In some cases, facial pain can also be associated with other symptoms such as headaches, redness, swelling, or changes in sensation. Accurate diagnosis and treatment of the underlying cause are essential for effective management of facial pain.
Vibrissae are stiff, tactile hairs that are highly sensitive to touch and movement. They are primarily found in various mammals, including humans (in the form of eyelashes and eyebrows), but they are especially prominent in certain animals such as cats, rats, and seals. These hairs are deeply embedded in skin and have a rich supply of nerve endings that provide the animal with detailed information about its environment. They are often used for detecting nearby objects, navigating in the dark, and maintaining balance.
Dihydroergotamine is a medication that belongs to a class of drugs called ergot alkaloids. It is a semi-synthetic derivative of ergotamine, which is found naturally in the ergot fungus. Dihydroergotamine is used to treat migraines and cluster headaches.
The drug works by narrowing blood vessels around the brain, which helps to reduce the pain and other symptoms associated with migraines and cluster headaches. It can be administered via injection, nasal spray, or oral tablet. Dihydroergotamine may cause serious side effects, including medication overuse headache, ergotism, and cardiovascular events such as heart attack or stroke. Therefore, it is important to use this medication only as directed by a healthcare provider.
Sumatriptan is a selective serotonin receptor agonist, specifically targeting the 5-HT1D and 5-HT1B receptors. It is primarily used to treat migraines and cluster headaches. Sumatriptan works by narrowing blood vessels around the brain and reducing inflammation that leads to migraine symptoms.
The medication comes in various forms, including tablets, injectables, and nasal sprays. Common side effects of sumatriptan include feelings of warmth or hotness, tingling, tightness, pressure, heaviness, pain, or burning in the neck, throat, jaw, chest, or arms.
It is important to note that sumatriptan should not be used if a patient has a history of heart disease, stroke, or uncontrolled high blood pressure. Additionally, it should not be taken within 24 hours of using another migraine medication containing ergotamine or similar drugs such as dihydroergotamine, methysergide, or caffeine-containing analgesics.
The trigeminal ganglion, also known as the semilunar or Gasserian ganglion, is a sensory ganglion (a cluster of nerve cell bodies) located near the base of the skull. It is a part of the trigeminal nerve (the fifth cranial nerve), which is responsible for sensation in the face and motor functions such as biting and chewing.
The trigeminal ganglion contains the cell bodies of sensory neurons that carry information from three major branches of the trigeminal nerve: the ophthalmic, maxillary, and mandibular divisions. These divisions provide sensation to different areas of the face, head, and oral cavity, including the skin, mucous membranes, muscles, and teeth.
Damage to the trigeminal ganglion or its nerve branches can result in various sensory disturbances, such as pain, numbness, or tingling in the affected areas. Conditions like trigeminal neuralgia, a disorder characterized by intense, stabbing facial pain, may involve the trigeminal ganglion and its associated nerves.
The brainstem is the lower part of the brain that connects to the spinal cord. It consists of the midbrain, pons, and medulla oblongata. The brainstem controls many vital functions such as heart rate, breathing, and blood pressure. It also serves as a relay center for sensory and motor information between the cerebral cortex and the rest of the body. Additionally, several cranial nerves originate from the brainstem, including those that control eye movements, facial movements, and hearing.
Afferent pathways, also known as sensory pathways, refer to the neural connections that transmit sensory information from the peripheral nervous system to the central nervous system (CNS), specifically to the brain and spinal cord. These pathways are responsible for carrying various types of sensory information, such as touch, temperature, pain, pressure, vibration, hearing, vision, and taste, to the CNS for processing and interpretation.
The afferent pathways begin with sensory receptors located throughout the body, which detect changes in the environment and convert them into electrical signals. These signals are then transmitted via afferent neurons, also known as sensory neurons, to the spinal cord or brainstem. Within the CNS, the information is further processed and integrated with other neural inputs before being relayed to higher cognitive centers for conscious awareness and response.
Understanding the anatomy and physiology of afferent pathways is essential for diagnosing and treating various neurological conditions that affect sensory function, such as neuropathies, spinal cord injuries, and brain disorders.
The meninges are the protective membranes that cover the brain and spinal cord. They consist of three layers: the dura mater (the outermost, toughest layer), the arachnoid mater (middle layer), and the pia mater (the innermost, delicate layer). These membranes provide protection and support to the central nervous system, and contain blood vessels that supply nutrients and remove waste products. Inflammation or infection of the meninges is called meningitis, which can be a serious medical condition requiring prompt treatment.
Wheat Germ Agglutinin (WGA) is a lectin protein found in wheat germ, which binds specifically to certain sugars on the surface of cells. Horseradish Peroxidase (HRP) is an enzyme derived from horseradish that catalyzes the conversion of certain substrates, producing a chemiluminescent or colorimetric signal.
A WGA-HRP conjugate refers to the formation of a covalent bond between WGA and HRP, creating an immunoconjugate. This complex is often used as a detection tool in various assays, such as ELISA (Enzyme-Linked Immunosorbent Assay) or Western blotting, where it can bind to specific carbohydrates on the target molecule and catalyze a colorimetric or chemiluminescent reaction, allowing for the visualization of the target.
The pons is a part of the brainstem that lies between the medulla oblongata and the midbrain. Its name comes from the Latin word "ponte" which means "bridge," as it serves to connect these two regions of the brainstem. The pons contains several important structures, including nerve fibers that carry signals between the cerebellum (the part of the brain responsible for coordinating muscle movements) and the rest of the nervous system. It also contains nuclei (clusters of neurons) that help regulate various functions such as respiration, sleep, and facial movements.
Afferent neurons, also known as sensory neurons, are a type of nerve cell that conducts impulses or signals from peripheral receptors towards the central nervous system (CNS), which includes the brain and spinal cord. These neurons are responsible for transmitting sensory information such as touch, temperature, pain, sound, and light to the CNS for processing and interpretation. Afferent neurons have specialized receptor endings that detect changes in the environment and convert them into electrical signals, which are then transmitted to the CNS via synapses with other neurons. Once the signals reach the CNS, they are processed and integrated with other information to produce a response or reaction to the stimulus.
The masseter muscle is a strong chewing muscle in the jaw. It is a broad, thick, quadrilateral muscle that extends from the zygomatic arch (cheekbone) to the lower jaw (mandible). The masseter muscle has two distinct parts: the superficial part and the deep part.
The superficial part of the masseter muscle originates from the lower border of the zygomatic process of the maxilla and the anterior two-thirds of the inferior border of the zygomatic arch. The fibers of this part run almost vertically downward to insert on the lateral surface of the ramus of the mandible and the coronoid process.
The deep part of the masseter muscle originates from the deep surface of the zygomatic arch and inserts on the medial surface of the ramus of the mandible, blending with the temporalis tendon.
The primary function of the masseter muscle is to elevate the mandible, helping to close the mouth and clench the teeth together during mastication (chewing). It also plays a role in stabilizing the jaw during biting and speaking. The masseter muscle is one of the most powerful muscles in the human body relative to its size.
The cochlear nucleus is the first relay station in the auditory pathway within the central nervous system. It is a structure located in the lower pons region of the brainstem and receives sensory information from the cochlea, which is the spiral-shaped organ of hearing in the inner ear.
The cochlear nucleus consists of several subdivisions, each with distinct neuronal populations that process different aspects of auditory information. These subdivisions include the anteroventral cochlear nucleus (AVCN), posteroventral cochlear nucleus (PVCN), dorsal cochlear nucleus (DCN), and the granule cell domain.
Neurons in these subdivisions perform various computations on the incoming auditory signals, such as frequency analysis, intensity coding, and sound localization. The output of the cochlear nucleus is then sent via several pathways to higher brain regions for further processing and interpretation, including the inferior colliculus, medial geniculate body, and eventually the auditory cortex.
Damage or dysfunction in the cochlear nucleus can lead to hearing impairments and other auditory processing disorders.
Central nervous system (CNS) sensitization refers to a state in which the CNS, specifically the brain and spinal cord, becomes increasingly hypersensitive to stimuli. This heightened sensitivity results in an amplified response to painful or non-painful stimuli.
In CNS sensitization, there is an increased responsiveness of neurons in the CNS, leading to a lower threshold for activation and an enhanced transmission of nociceptive (pain) signals. This can occur due to various factors such as tissue injury, inflammation, or nerve damage, which trigger changes in the nervous system that contribute to the development and maintenance of chronic pain conditions.
CNS sensitization is associated with functional and structural reorganization within the CNS, including alterations in neurotransmitter release, ion channel function, and synaptic plasticity. These changes can result in long-term modifications in the processing and perception of pain, making it more difficult to manage and treat chronic pain conditions.
Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.
Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.
These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.
Nociceptors are specialized peripheral sensory neurons that detect and transmit signals indicating potentially harmful stimuli in the form of pain. They are activated by various noxious stimuli such as extreme temperatures, intense pressure, or chemical irritants. Once activated, nociceptors transmit these signals to the central nervous system (spinal cord and brain) where they are interpreted as painful sensations, leading to protective responses like withdrawing from the harmful stimulus or seeking medical attention. Nociceptors play a crucial role in our perception of pain and help protect the body from further harm.
Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.
Proto-oncogene proteins, such as c-Fos, are normal cellular proteins that play crucial roles in various biological processes including cell growth, differentiation, and survival. They can be activated or overexpressed due to genetic alterations, leading to the formation of cancerous cells. The c-Fos protein is a nuclear phosphoprotein involved in signal transduction pathways and forms a heterodimer with c-Jun to create the activator protein-1 (AP-1) transcription factor complex. This complex binds to specific DNA sequences, thereby regulating the expression of target genes that contribute to various cellular responses, including proliferation, differentiation, and apoptosis. Dysregulation of c-Fos can result in uncontrolled cell growth and malignant transformation, contributing to tumor development and progression.
Physical stimulation, in a medical context, refers to the application of external forces or agents to the body or its tissues to elicit a response. This can include various forms of touch, pressure, temperature, vibration, or electrical currents. The purpose of physical stimulation may be therapeutic, as in the case of massage or physical therapy, or diagnostic, as in the use of reflex tests. It is also used in research settings to study physiological responses and mechanisms.
In a broader sense, physical stimulation can also refer to the body's exposure to physical activity or exercise, which can have numerous health benefits, including improving cardiovascular function, increasing muscle strength and flexibility, and reducing the risk of chronic diseases.
The medulla oblongata is a part of the brainstem that is located in the posterior portion of the brainstem and continues with the spinal cord. It plays a vital role in controlling several critical bodily functions, such as breathing, heart rate, and blood pressure. The medulla oblongata also contains nerve pathways that transmit sensory information from the body to the brain and motor commands from the brain to the muscles. Additionally, it is responsible for reflexes such as vomiting, swallowing, coughing, and sneezing.
Dura Mater is the thickest and outermost of the three membranes (meninges) that cover the brain and spinal cord. It provides protection and support to these delicate structures. The other two layers are called the Arachnoid Mater and the Pia Mater, which are thinner and more delicate than the Dura Mater. Together, these three layers form a protective barrier around the central nervous system.
Stilbamidines are a class of chemical compounds that are primarily used as veterinary medicines, specifically as parasiticides for the treatment and prevention of ectoparasites such as ticks and lice in livestock animals. Stilbamidines belong to the family of chemicals known as formamidines, which are known to have insecticidal and acaricidal properties.
The most common stilbamidine compound is chlorphentermine, which has been used as an appetite suppressant in human medicine. However, its use as a weight loss drug was discontinued due to its addictive properties and potential for serious side effects.
It's important to note that Stilbamidines are not approved for use in humans and should only be used under the supervision of a veterinarian for the intended purpose of treating and preventing ectoparasites in animals.
Dental pulp is the soft tissue located in the center of a tooth, surrounded by the dentin. It contains nerves, blood vessels, and connective tissue, and plays a vital role in the development and health of the tooth. The dental pulp helps to form dentin during tooth development and continues to provide nourishment to the tooth throughout its life. It also serves as a sensory organ, allowing the tooth to detect hot and cold temperatures and transmit pain signals to the brain. Injury or infection of the dental pulp can lead to serious dental problems, such as tooth decay or abscesses, and may require root canal treatment to remove the damaged tissue and save the tooth.
Substantia gelatinosa (SG) is a term used in anatomy to refer to a part of the gray matter in the dorsal horn of the spinal cord. It's located in the most posterior and lateral portion of the dorsal horn, and it is characterized by its gelatinous appearance due to the high content of neuroglial cells and neuropil.
The substantia gelatinosa plays a crucial role in sensory processing, particularly in pain perception. It contains a variety of neurons that receive input from primary afferent fibers (both myelinated Aδ and unmyelinated C fibers) carrying nociceptive information from the periphery. The SG also contains interneurons that modulate the transmission of these nociceptive signals to higher brain centers, thus contributing to the complex processing of pain.
Furthermore, the substantia gelatinosa is involved in the regulation of autonomic functions and temperature sensation. It's worth noting that the term "substantia gelatinosa" is sometimes used interchangeably with "lamina II," as they refer to the same anatomical structure. However, some sources prefer to differentiate between them by using "substantia gelatinosa" for the entire region and "lamina II" specifically for the cellular layer of this region.
Neural pathways, also known as nerve tracts or fasciculi, refer to the highly organized and specialized routes through which nerve impulses travel within the nervous system. These pathways are formed by groups of neurons (nerve cells) that are connected in a series, creating a continuous communication network for electrical signals to transmit information between different regions of the brain, spinal cord, and peripheral nerves.
Neural pathways can be classified into two main types: sensory (afferent) and motor (efferent). Sensory neural pathways carry sensory information from various receptors in the body (such as those for touch, temperature, pain, and vision) to the brain for processing. Motor neural pathways, on the other hand, transmit signals from the brain to the muscles and glands, controlling movements and other effector functions.
The formation of these neural pathways is crucial for normal nervous system function, as it enables efficient communication between different parts of the body and allows for complex behaviors, cognitive processes, and adaptive responses to internal and external stimuli.
Capsaicin is defined in medical terms as the active component of chili peppers (genus Capsicum) that produces a burning sensation when it comes into contact with mucous membranes or skin. It is a potent irritant and is used topically as a counterirritant in some creams and patches to relieve pain. Capsaicin works by depleting substance P, a neurotransmitter that relays pain signals to the brain, from nerve endings.
Here is the medical definition of capsaicin from the Merriam-Webster's Medical Dictionary:
caпсаісіn : an alkaloid (C18H27NO3) that is the active principle of red peppers and is used in topical preparations as a counterirritant and analgesic.
Electric stimulation, also known as electrical nerve stimulation or neuromuscular electrical stimulation, is a therapeutic treatment that uses low-voltage electrical currents to stimulate nerves and muscles. It is often used to help manage pain, promote healing, and improve muscle strength and mobility. The electrical impulses can be delivered through electrodes placed on the skin or directly implanted into the body.
In a medical context, electric stimulation may be used for various purposes such as:
1. Pain management: Electric stimulation can help to block pain signals from reaching the brain and promote the release of endorphins, which are natural painkillers produced by the body.
2. Muscle rehabilitation: Electric stimulation can help to strengthen muscles that have become weak due to injury, illness, or surgery. It can also help to prevent muscle atrophy and improve range of motion.
3. Wound healing: Electric stimulation can promote tissue growth and help to speed up the healing process in wounds, ulcers, and other types of injuries.
4. Urinary incontinence: Electric stimulation can be used to strengthen the muscles that control urination and reduce symptoms of urinary incontinence.
5. Migraine prevention: Electric stimulation can be used as a preventive treatment for migraines by applying electrical impulses to specific nerves in the head and neck.
It is important to note that electric stimulation should only be administered under the guidance of a qualified healthcare professional, as improper use can cause harm or discomfort.
Vesicular Glutamate Transport Protein 2 (VGLUT2) is a type of protein responsible for transporting the neurotransmitter glutamate from the cytoplasm into synaptic vesicles within neurons. This protein is specifically located in the presynaptic terminals and plays a crucial role in the packaging, storage, and release of glutamate, which is the primary excitatory neurotransmitter in the central nervous system.
Glutamate is involved in various physiological functions, such as learning, memory, and synaptic plasticity. Dysfunction of VGLUT2 has been implicated in several neurological disorders, including epilepsy, chronic pain, and neurodevelopmental conditions like autism and schizophrenia.
Calcitonin gene-related peptide (CGRP) receptors are a type of cell surface receptor found in various tissues and cells, including the nervous system and blood vessels. CGRP is a neuropeptide that plays a role in regulating vasodilation, inflammation, and nociception (the sensation of pain).
The CGRP receptor is a complex of two proteins: calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein 1 (RAMP1). When CGRP binds to the CLR-RAMP1 complex, it activates a signaling pathway that leads to vasodilation and increased pain sensitivity.
CGRP receptors have been identified as important targets for the treatment of migraine headaches, as CGRP levels are known to increase during migraine attacks. Several drugs that target CGRP receptors have been developed and approved for the prevention and acute treatment of migraines.
Cortical Spreading Depression (CSD) is a wave of neuronal and glial depolarization that spreads across the cerebral cortex, characterized by the near-complete suppression of neural activity, followed by a period of depressed excitability. It is often accompanied by profound changes in blood flow and metabolism.
CSD is associated with several neurological conditions, including migraine with aura, traumatic brain injury, and subarachnoid hemorrhage. In migraine, it is believed to underlie the visual aura that precedes the headache phase of the attack. CSD can also have harmful effects on the brain, contributing to the development of secondary injuries after trauma or stroke.
The underlying mechanisms of CSD involve the activation of various ion channels and neurotransmitter receptors, leading to a massive efflux of potassium ions (K+) from neurons and glial cells. This K+ efflux triggers a cascade of events that result in the depolarization of surrounding neurons and glia, ultimately leading to the suppression of neural activity and the characteristic hemodynamic and metabolic changes associated with CSD.
"Cat" is a common name that refers to various species of small carnivorous mammals that belong to the family Felidae. The domestic cat, also known as Felis catus or Felis silvestris catus, is a popular pet and companion animal. It is a subspecies of the wildcat, which is found in Europe, Africa, and Asia.
Domestic cats are often kept as pets because of their companionship, playful behavior, and ability to hunt vermin. They are also valued for their ability to provide emotional support and therapy to people. Cats are obligate carnivores, which means that they require a diet that consists mainly of meat to meet their nutritional needs.
Cats are known for their agility, sharp senses, and predatory instincts. They have retractable claws, which they use for hunting and self-defense. Cats also have a keen sense of smell, hearing, and vision, which allow them to detect prey and navigate their environment.
In medical terms, cats can be hosts to various parasites and diseases that can affect humans and other animals. Some common feline diseases include rabies, feline leukemia virus (FeLV), feline immunodeficiency virus (FIV), and toxoplasmosis. It is important for cat owners to keep their pets healthy and up-to-date on vaccinations and preventative treatments to protect both the cats and their human companions.
Masticatory muscles are a group of skeletal muscles responsible for the mastication (chewing) process in humans and other animals. They include:
1. Masseter muscle: This is the primary muscle for chewing and is located on the sides of the face, running from the lower jawbone (mandible) to the cheekbone (zygomatic arch). It helps close the mouth and elevate the mandible during chewing.
2. Temporalis muscle: This muscle is situated in the temporal region of the skull, covering the temple area. It assists in closing the jaw, retracting the mandible, and moving it sideways during chewing.
3. Medial pterygoid muscle: Located deep within the cheek, near the angle of the lower jaw, this muscle helps move the mandible forward and grind food during chewing. It also contributes to closing the mouth.
4. Lateral pterygoid muscle: Found inside the ramus (the vertical part) of the mandible, this muscle has two heads - superior and inferior. The superior head helps open the mouth by pulling the temporomandibular joint (TMJ) downwards, while the inferior head assists in moving the mandible sideways during chewing.
These muscles work together to enable efficient chewing and food breakdown, preparing it for swallowing and digestion.
Nerve fibers are specialized structures that constitute the long, slender processes (axons) of neurons (nerve cells). They are responsible for conducting electrical impulses, known as action potentials, away from the cell body and transmitting them to other neurons or effector organs such as muscles and glands. Nerve fibers are often surrounded by supportive cells called glial cells and are grouped together to form nerve bundles or nerves. These fibers can be myelinated (covered with a fatty insulating sheath called myelin) or unmyelinated, which influences the speed of impulse transmission.
Mechanoreceptors are specialized sensory receptor cells that convert mechanical stimuli such as pressure, tension, or deformation into electrical signals that can be processed and interpreted by the nervous system. They are found in various tissues throughout the body, including the skin, muscles, tendons, joints, and internal organs. Mechanoreceptors can detect different types of mechanical stimuli depending on their specific structure and location. For example, Pacinian corpuscles in the skin respond to vibrations, while Ruffini endings in the joints detect changes in joint angle and pressure. Overall, mechanoreceptors play a crucial role in our ability to perceive and interact with our environment through touch, proprioception (the sense of the position and movement of body parts), and visceral sensation (awareness of internal organ activity).
The mesencephalon, also known as the midbrain, is the middle portion of the brainstem that connects the hindbrain (rhombencephalon) and the forebrain (prosencephalon). It plays a crucial role in several important functions including motor control, vision, hearing, and the regulation of consciousness and sleep-wake cycles. The mesencephalon contains several important structures such as the cerebral aqueduct, tectum, tegmentum, cerebral peduncles, and several cranial nerve nuclei (III and IV).
In medical terms, the jaw is referred to as the mandible (in humans and some other animals), which is the lower part of the face that holds the lower teeth in place. It's a large, horseshoe-shaped bone that forms the lower jaw and serves as a attachment point for several muscles that are involved in chewing and moving the lower jaw.
In addition to the mandible, the upper jaw is composed of two bones known as the maxillae, which fuse together at the midline of the face to form the upper jaw. The upper jaw holds the upper teeth in place and forms the roof of the mouth, as well as a portion of the eye sockets and nasal cavity.
Together, the mandible and maxillae allow for various functions such as speaking, eating, and breathing.
Calcitonin gene-related peptide (CGRP) is a neurotransmitter and vasodilator peptide that is widely distributed in the nervous system. It is encoded by the calcitonin gene, which also encodes calcitonin and catestatin. CGRP is produced and released by sensory nerves and plays important roles in pain transmission, modulation of inflammation, and regulation of blood flow.
CGRP exists as two forms, α-CGRP and β-CGRP, which differ slightly in their amino acid sequences but have similar biological activities. α-CGRP is found primarily in the central and peripheral nervous systems, while β-CGRP is expressed mainly in the gastrointestinal tract.
CGRP exerts its effects by binding to specific G protein-coupled receptors, which are widely distributed in various tissues, including blood vessels, smooth muscles, and sensory neurons. Activation of CGRP receptors leads to increased intracellular cyclic AMP levels, activation of protein kinase A, and subsequent relaxation of vascular smooth muscle, resulting in vasodilation.
CGRP has been implicated in several clinical conditions, including migraine, cluster headache, and inflammatory pain. Inhibition of CGRP signaling has emerged as a promising therapeutic strategy for the treatment of these disorders.
A migraine disorder is a neurological condition characterized by recurrent headaches that often involve one side of the head and are accompanied by various symptoms such as nausea, vomiting, sensitivity to light and sound, and visual disturbances. Migraines can last from several hours to days and can be severely debilitating. The exact cause of migraines is not fully understood, but they are believed to result from a combination of genetic and environmental factors that affect the brain and blood vessels. There are different types of migraines, including migraine without aura, migraine with aura, chronic migraine, and others, each with its own specific set of symptoms and diagnostic criteria. Treatment typically involves a combination of lifestyle changes, medications, and behavioral therapies to manage symptoms and prevent future attacks.
The somatosensory cortex is a part of the brain located in the postcentral gyrus of the parietal lobe, which is responsible for processing sensory information from the body. It receives and integrates tactile, proprioceptive, and thermoception inputs from the skin, muscles, joints, and internal organs, allowing us to perceive and interpret touch, pressure, pain, temperature, vibration, position, and movement of our body parts. The somatosensory cortex is organized in a map-like manner, known as the sensory homunculus, where each body part is represented according to its relative sensitivity and density of innervation. This organization allows for precise localization and discrimination of tactile stimuli across the body surface.
Evoked potentials (EPs) are medical tests that measure the electrical activity in the brain or spinal cord in response to specific sensory stimuli, such as sight, sound, or touch. These tests are often used to help diagnose and monitor conditions that affect the nervous system, such as multiple sclerosis, brainstem tumors, and spinal cord injuries.
There are several types of EPs, including:
1. Visual Evoked Potentials (VEPs): These are used to assess the function of the visual pathway from the eyes to the back of the brain. A patient is typically asked to look at a patterned image or flashing light while electrodes placed on the scalp record the electrical responses.
2. Brainstem Auditory Evoked Potentials (BAEPs): These are used to evaluate the function of the auditory nerve and brainstem. Clicking sounds are presented to one or both ears, and electrodes placed on the scalp measure the response.
3. Somatosensory Evoked Potentials (SSEPs): These are used to assess the function of the peripheral nerves and spinal cord. Small electrical shocks are applied to a nerve at the wrist or ankle, and electrodes placed on the scalp record the response as it travels up the spinal cord to the brain.
4. Motor Evoked Potentials (MEPs): These are used to assess the function of the motor pathways in the brain and spinal cord. A magnetic or electrical stimulus is applied to the brain or spinal cord, and electrodes placed on a muscle measure the response as it travels down the motor pathway.
EPs can help identify abnormalities in the nervous system that may not be apparent through other diagnostic tests, such as imaging studies or clinical examinations. They are generally safe, non-invasive procedures with few risks or side effects.
The nucleus accumbens is a part of the brain that is located in the ventral striatum, which is a key region of the reward circuitry. It is made up of two subregions: the shell and the core. The nucleus accumbens receives inputs from various sources, including the prefrontal cortex, amygdala, and hippocampus, and sends outputs to the ventral pallidum and other areas.
The nucleus accumbens is involved in reward processing, motivation, reinforcement learning, and addiction. It plays a crucial role in the release of the neurotransmitter dopamine, which is associated with pleasure and reinforcement. Dysfunction in the nucleus accumbens has been implicated in various neurological and psychiatric conditions, including substance use disorders, depression, and obsessive-compulsive disorder.
The thalamus is a large, paired structure in the brain that serves as a relay station for sensory and motor signals to the cerebral cortex. It is located in the dorsal part of the diencephalon and is made up of two symmetrical halves, each connected to the corresponding cerebral hemisphere.
The thalamus receives inputs from almost all senses, except for the olfactory system, and processes them before sending them to specific areas in the cortex. It also plays a role in regulating consciousness, sleep, and alertness. Additionally, the thalamus is involved in motor control by relaying information between the cerebellum and the motor cortex.
The thalamus is divided into several nuclei, each with distinct connections and functions. Some of these nuclei are involved in sensory processing, while others are involved in motor function or regulation of emotions and cognition. Overall, the thalamus plays a critical role in integrating information from various brain regions and modulating cognitive and emotional processes.
The temporomandibular joint (TMJ) is the articulation between the mandible (lower jaw) and the temporal bone of the skull. It's a complex joint that involves the movement of two bones, several muscles, and various ligaments. The TMJ allows for movements like rotation and translation, enabling us to open and close our mouth, chew, speak, and yawn. Dysfunction in this joint can lead to temporomandibular joint disorders (TMD), which can cause pain, discomfort, and limited jaw movement.
An action potential is a brief electrical signal that travels along the membrane of a nerve cell (neuron) or muscle cell. It is initiated by a rapid, localized change in the permeability of the cell membrane to specific ions, such as sodium and potassium, resulting in a rapid influx of sodium ions and a subsequent efflux of potassium ions. This ion movement causes a brief reversal of the electrical potential across the membrane, which is known as depolarization. The action potential then propagates along the cell membrane as a wave, allowing the electrical signal to be transmitted over long distances within the body. Action potentials play a crucial role in the communication and functioning of the nervous system and muscle tissue.
Thalamic nuclei refer to specific groupings of neurons within the thalamus, a key relay station in the brain that receives sensory information from various parts of the body and transmits it to the cerebral cortex for processing. The thalamus is divided into several distinct nuclei, each with its own unique functions and connections. These nuclei can be broadly categorized into three groups:
1. Sensory relay nuclei: These nuclei receive sensory information from different modalities such as vision, audition, touch, and taste, and project this information to specific areas of the cerebral cortex for further processing. Examples include the lateral geniculate nucleus (vision), medial geniculate nucleus (audition), and ventral posterior nucleus (touch and taste).
2. Association nuclei: These nuclei are involved in higher-order cognitive functions, such as attention, memory, and executive control. They receive inputs from various cortical areas and project back to those same areas, forming closed loops that facilitate information processing and integration. Examples include the mediodorsal nucleus and pulvinar.
3. Motor relay nuclei: These nuclei are involved in motor control and coordination. They receive inputs from the cerebral cortex and basal ganglia and project to the brainstem and spinal cord, helping to regulate movement and posture. Examples include the ventral anterior and ventral lateral nuclei.
Overall, thalamic nuclei play a crucial role in integrating sensory, motor, and cognitive information, allowing for adaptive behavior and conscious experience.
The solitary nucleus, also known as the nucleus solitarius, is a collection of neurons located in the medulla oblongata region of the brainstem. It plays a crucial role in the processing and integration of sensory information, particularly taste and visceral afferent fibers from internal organs. The solitary nucleus receives inputs from various cranial nerves, including the glossopharyngeal (cranial nerve IX) and vagus nerves (cranial nerve X), and is involved in reflex responses related to swallowing, vomiting, and cardiovascular regulation.
Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.
Serotonin receptor agonists are a class of medications that bind to and activate serotonin receptors in the body, mimicking the effects of the neurotransmitter serotonin. These drugs can have various effects depending on which specific serotonin receptors they act upon. Some serotonin receptor agonists are used to treat conditions such as migraines, cluster headaches, and Parkinson's disease, while others may be used to stimulate appetite or reduce anxiety. It is important to note that some serotonin receptor agonists can have serious side effects, particularly when taken in combination with other medications that affect serotonin levels, such as selective serotonin reuptake inhibitors (SSRIs) or monoamine oxidase inhibitors (MAOIs). This can lead to a condition called serotonin syndrome, which is characterized by symptoms such as agitation, confusion, rapid heart rate, high blood pressure, and muscle stiffness.
Neural inhibition is a process in the nervous system that decreases or prevents the activity of neurons (nerve cells) in order to regulate and control communication within the nervous system. It is a fundamental mechanism that allows for the balance of excitation and inhibition necessary for normal neural function. Inhibitory neurotransmitters, such as GABA (gamma-aminobutyric acid) and glycine, are released from the presynaptic neuron and bind to receptors on the postsynaptic neuron, reducing its likelihood of firing an action potential. This results in a decrease in neural activity and can have various effects depending on the specific neurons and brain regions involved. Neural inhibition is crucial for many functions including motor control, sensory processing, attention, memory, and emotional regulation.
The spinal cord is a major part of the nervous system, extending from the brainstem and continuing down to the lower back. It is a slender, tubular bundle of nerve fibers (axons) and support cells (glial cells) that carries signals between the brain and the rest of the body. The spinal cord primarily serves as a conduit for motor information, which travels from the brain to the muscles, and sensory information, which travels from the body to the brain. It also contains neurons that can independently process and respond to information within the spinal cord without direct input from the brain.
The spinal cord is protected by the bony vertebral column (spine) and is divided into 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each segment corresponds to a specific region of the body and gives rise to pairs of spinal nerves that exit through the intervertebral foramina at each level.
The spinal cord is responsible for several vital functions, including:
1. Reflexes: Simple reflex actions, such as the withdrawal reflex when touching a hot surface, are mediated by the spinal cord without involving the brain.
2. Muscle control: The spinal cord carries motor signals from the brain to the muscles, enabling voluntary movement and muscle tone regulation.
3. Sensory perception: The spinal cord transmits sensory information, such as touch, temperature, pain, and vibration, from the body to the brain for processing and awareness.
4. Autonomic functions: The sympathetic and parasympathetic divisions of the autonomic nervous system originate in the thoracolumbar and sacral regions of the spinal cord, respectively, controlling involuntary physiological responses like heart rate, blood pressure, digestion, and respiration.
Damage to the spinal cord can result in various degrees of paralysis or loss of sensation below the level of injury, depending on the severity and location of the damage.
"Newborn animals" refers to the very young offspring of animals that have recently been born. In medical terminology, newborns are often referred to as "neonates," and they are classified as such from birth until about 28 days of age. During this time period, newborn animals are particularly vulnerable and require close monitoring and care to ensure their survival and healthy development.
The specific needs of newborn animals can vary widely depending on the species, but generally, they require warmth, nutrition, hydration, and protection from harm. In many cases, newborns are unable to regulate their own body temperature or feed themselves, so they rely heavily on their mothers for care and support.
In medical settings, newborn animals may be examined and treated by veterinarians to ensure that they are healthy and receiving the care they need. This can include providing medical interventions such as feeding tubes, antibiotics, or other treatments as needed to address any health issues that arise. Overall, the care and support of newborn animals is an important aspect of animal medicine and conservation efforts.
"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.
Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.
Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.
Posterior horn cells refer to the neurons located in the posterior (or dorsal) horn of the gray matter in the spinal cord. These cells are primarily responsible for receiving and processing sensory information from peripheral nerves, particularly related to touch, pressure, pain, and temperature. The axons of these cells form the ascending tracts that carry this information to the brain for further processing. It's worth noting that damage to posterior horn cells can result in various sensory deficits, such as those seen in certain neurological conditions.
The Raphe Nuclei are clusters of neurons located in the brainstem, specifically in the midline of the pons, medulla oblongata, and mesencephalon (midbrain). These neurons are characterized by their ability to synthesize and release serotonin, a neurotransmitter that plays a crucial role in regulating various functions such as mood, appetite, sleep, and pain perception.
The Raphe Nuclei project axons widely throughout the central nervous system, allowing serotonin to modulate the activity of other neurons. There are several subdivisions within the Raphe Nuclei, each with distinct connections and functions. Dysfunction in the Raphe Nuclei has been implicated in several neurological and psychiatric disorders, including depression, anxiety, and chronic pain.
The cerebellar nuclei are clusters of neurons located within the white matter of the cerebellum, a region of the brain responsible for motor coordination, balance, and fine movement regulation. There are four main pairs of cerebellar nuclei: the fastigial, interpositus, dentate, and vestibular nuclei. These nuclei receive input from various parts of the cerebellar cortex and project to different areas of the brainstem and thalamus, contributing to the regulation of muscle tone, posture, and movement.
The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:
1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.
The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.
The septal nuclei are a collection of gray matter structures located in the basal forebrain, specifically in the septum pellucidum. They consist of several interconnected subnuclei that play important roles in various functions such as reward and reinforcement, emotional processing, learning, and memory.
The septal nuclei are primarily composed of GABAergic neurons (neurons that release the neurotransmitter gamma-aminobutyric acid or GABA) and receive inputs from several brain regions, including the hippocampus, amygdala, hypothalamus, and prefrontal cortex. They also send projections to various areas, including the thalamus, hypothalamus, and other limbic structures.
Stimulation of the septal nuclei has been associated with feelings of pleasure and reward, while damage or lesions can lead to changes in emotional behavior and cognitive functions. The septal nuclei are also involved in neuroendocrine regulation, particularly in relation to the hypothalamic-pituitary-adrenal (HPA) axis and the release of stress hormones.
I'm sorry for any confusion, but "Active Transport, Cell Nucleus" is not a widely recognized or established medical term. Active transport typically refers to the energy-dependent process by which cells move molecules across their membranes against their concentration gradient. This process is facilitated by transport proteins and requires ATP as an energy source. However, this process primarily occurs in the cell membrane and not in the cell nucleus.
The cell nucleus, on the other hand, contains genetic material (DNA) and is responsible for controlling various cellular activities such as gene expression, replication, and repair. While there are transport processes that occur within the nucleus, they do not typically involve active transport in the same way that it occurs at the cell membrane.
Therefore, a medical definition of "Active Transport, Cell Nucleus" would not be applicable or informative in this context.
The arcuate nucleus is a part of the hypothalamus in the brain. It is involved in the regulation of various physiological functions, including appetite, satiety, and reproductive hormones. The arcuate nucleus contains two main types of neurons: those that produce neuropeptide Y and agouti-related protein, which stimulate feeding and reduce energy expenditure; and those that produce pro-opiomelanocortin and cocaine-and-amphetamine-regulated transcript, which suppress appetite and increase energy expenditure. These neurons communicate with other parts of the brain to help maintain energy balance and reproductive function.
The caudate nucleus is a part of the brain located within the basal ganglia, a group of structures that are important for movement control and cognition. It has a distinctive C-shaped appearance and plays a role in various functions such as learning, memory, emotion, and motivation. The caudate nucleus receives inputs from several areas of the cerebral cortex and sends outputs to other basal ganglia structures, contributing to the regulation of motor behavior and higher cognitive processes.
The Paraventricular Hypothalamic Nucleus (PVN) is a nucleus in the hypothalamus, which is a part of the brain that regulates various autonomic functions and homeostatic processes. The PVN plays a crucial role in the regulation of neuroendocrine and autonomic responses to stress, as well as the control of fluid and electrolyte balance, cardiovascular function, and energy balance.
The PVN is composed of several subdivisions, including the magnocellular and parvocellular divisions. The magnocellular neurons produce and release two neuropeptides, oxytocin and vasopressin (also known as antidiuretic hormone), into the circulation via the posterior pituitary gland. These neuropeptides play important roles in social behavior, reproduction, and fluid balance.
The parvocellular neurons, on the other hand, project to various brain regions and the pituitary gland, where they release neurotransmitters and neuropeptides that regulate the hypothalamic-pituitary-adrenal (HPA) axis, which is responsible for the stress response. The PVN also contains neurons that produce corticotropin-releasing hormone (CRH), a key neurotransmitter involved in the regulation of the HPA axis and the stress response.
Overall, the Paraventricular Hypothalamic Nucleus is an essential component of the brain's regulatory systems that help maintain homeostasis and respond to stressors. Dysfunction of the PVN has been implicated in various pathological conditions, including hypertension, obesity, and mood disorders.
Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. It is a complex phenomenon that can result from various stimuli, such as thermal, mechanical, or chemical irritation, and it can be acute or chronic. The perception of pain involves the activation of specialized nerve cells called nociceptors, which transmit signals to the brain via the spinal cord. These signals are then processed in different regions of the brain, leading to the conscious experience of pain. It's important to note that pain is a highly individual and subjective experience, and its perception can vary widely among individuals.
Electrophysiology is a branch of medicine that deals with the electrical activities of the body, particularly the heart. In a medical context, electrophysiology studies (EPS) are performed to assess abnormal heart rhythms (arrhythmias) and to evaluate the effectiveness of certain treatments, such as medication or pacemakers.
During an EPS, electrode catheters are inserted into the heart through blood vessels in the groin or neck. These catheters can record the electrical activity of the heart and stimulate it to help identify the source of the arrhythmia. The information gathered during the study can help doctors determine the best course of treatment for each patient.
In addition to cardiac electrophysiology, there are also other subspecialties within electrophysiology, such as neuromuscular electrophysiology, which deals with the electrical activity of the nervous system and muscles.
Brain mapping is a broad term that refers to the techniques used to understand the structure and function of the brain. It involves creating maps of the various cognitive, emotional, and behavioral processes in the brain by correlating these processes with physical locations or activities within the nervous system. Brain mapping can be accomplished through a variety of methods, including functional magnetic resonance imaging (fMRI), positron emission tomography (PET) scans, electroencephalography (EEG), and others. These techniques allow researchers to observe which areas of the brain are active during different tasks or thoughts, helping to shed light on how the brain processes information and contributes to our experiences and behaviors. Brain mapping is an important area of research in neuroscience, with potential applications in the diagnosis and treatment of neurological and psychiatric disorders.
The suprachiasmatic nucleus (SCN) is a small region located in the hypothalamus of the brain, just above the optic chiasm where the optic nerves from each eye cross. It is considered to be the primary circadian pacemaker in mammals, responsible for generating and maintaining the body's internal circadian rhythm, which is a roughly 24-hour cycle that regulates various physiological processes such as sleep-wake cycles, hormone release, and metabolism.
The SCN receives direct input from retinal ganglion cells, which are sensitive to light and dark signals. This information helps the SCN synchronize the internal circadian rhythm with the external environment, allowing it to adjust to changes in day length and other environmental cues. The SCN then sends signals to other parts of the brain and body to regulate various functions according to the time of day.
Disruption of the SCN's function can lead to a variety of circadian rhythm disorders, such as jet lag, shift work disorder, and advanced or delayed sleep phase syndrome.
The red nucleus is a round-shaped collection of neurons located in the midbrain, specifically in the rostral part of the mesencephalon. It is called "red" due to its deep red color, which comes from the rich vascularization and numerous iron-containing red blood cells present in the region.
The red nucleus plays a crucial role in the motor system, primarily involved in controlling and coordinating movements, particularly on the contralateral side of the body. It is part of the rubrospinal tract, which descends from the red nucleus to the spinal cord and helps regulate fine motor movements and muscle tone.
There are two main types of neurons present in the red nucleus: magnocellular (large cells) and parvocellular (small cells). Magnocellular neurons form the rubrospinal tract, while parvocellular neurons project to the inferior olivary nucleus, which is part of the cerebellum. The connections between the red nucleus, cerebellum, and spinal cord allow for the integration and coordination of motor information and the execution of smooth movements.
Damage to the red nucleus can result in various motor impairments, such as ataxia (lack of muscle coordination), tremors, and weakness on the contralateral side of the body.
In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.
For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.
Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.
Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.
Trigeminal nerve nuclei
Spinal trigeminal nucleus
Trigeminal motor nucleus
Mesencephalic nucleus of trigeminal nerve
Principal sensory nucleus of trigeminal nerve
Cranial nerve nucleus
Denis John Williams
Axo-axonic synapse
Dentomandibular sensorimotor dysfunction
Cat senses
Alan M. Roberts
Medulla oblongata
Star-nosed mole
Trigeminocerebellar fibers
Rodolfo Llinás
Stem-cell niche
Cre-Lox recombination
Superior ganglion of vagus nerve
Barrel cortex
Dorsal column nuclei
Inferior ganglion of vagus nerve
Inferior ganglion of glossopharyngeal nerve
Parvocellular reticular nucleus
Rhombomere
Cranial nerves
Trigeminal lemniscus
Medial medullary syndrome
Jaw jerk reflex
Brainstem
SUNCT syndrome
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Mesencephalic nucleus4
- They include the nucleus of the spinal trigeminal tract ( TRIGEMINAL NUCLEUS, SPINAL ), the principal sensory nucleus, the mesencephalic nucleus, and the motor nucleus. (nih.gov)
- The sensory neurons of the trigeminal mesencephalic nucleus sending axons to the trigeminal motor nucleus, which in turn innervates the master muscle. (standardofcare.com)
- The mesencephalic nucleus is in the midbrain and receives proprioceptive fibers from all muscles of mastication. (medscape.com)
- They terminate in the mesencephalic nucleus. (medscape.com)
Caudalis7
- that is, the level of 5-HT was increased in the rostroventromedial medulla (RVM) and trigeminal nucleus caudalis (TNC) region and decreased in the plasma. (hindawi.com)
- In the central nervous system (CNS), the serotonergic system from the brainstem rostroventromedial medulla (RVM) region, including the nucleus raphe magnus (NRM) and nucleus reticularis paragigantocellularis (NpGC) nuclei, has descending projections to the trigeminal nucleus caudalis (TNC) and widespread projections to the forebrain through the periaqueductal gray (PAG) [ 18 ]. (hindawi.com)
- This study determined whether rapamycin, an mTOR inhibitor, reduces noci-ceptive responses and the number of Fos-immunoreactive (Fos-ir) cells in the trigem-inal nucleus caudalis (TNC) in a mouse orofacial formalin model. (kyobobook.co.kr)
- These afferents then project to the trigeminal nucleus caudalis, the thalamus, and to the cortex [85, 86] . (researchgate.net)
- Most scientists accept that it involves activation and sensitization of the trigeminovascular system, which includes the sensory peripheral projections to the pain-producing dura mater, and a central projection to the trigeminal nucleus caudalis and its cervical extension, the trigeminocervical complex (TCC). (medscape.com)
- It is thought that sensory input from the GON and the ophthalmic branch of the trigeminal nerve converges into the trigeminal nucleus caudalis, which is hypothesized to be the reason why occipital neuralgia is sometimes associated with migraine headache symptomatology. (medscape.com)
- [ 6 ] GON block decreases afferent input to the trigeminal nucleus caudalis, resulting in central pain modulation and reducing neuronal hyperexcitability at the level of second-order neurons. (medscape.com)
Ganglion7
- We compared the distribution of 5-HT 1D receptor-immunoreactive (5-HT 1D -IR) peripheral afferents within the trigeminal ganglion (TRG) and lumbar dorsal root ganglion (DRG) of the rat. (jneurosci.org)
- Through the pterygopalatine ganglion, this causes ocular vasodilation and activation of ocular trigeminal afferents through the trigemino-autonomic reflex [85]. (researchgate.net)
- For example, the trigeminal ganglion is superficial to the temporal bone whereas its associated nerve is attached to the mid-pons region of the brain stem. (lumenlearning.com)
- Calcium responses of chick trigeminal ganglion neurons to methyl anthranilate and capsaicin. (drexel.edu)
- The main sensory nucleus receives its afferents (as the sensory root) from the semilunar ganglion through the lateral part of the pons ventral surface. (medscape.com)
- The descending sensory fibers from the semilunar ganglion course through the pons and medulla in the spinal tract of CN V to end in the nuclei of this tract (as far as the second cervical segment). (medscape.com)
- The semilunar (gasserian or trigeminal) ganglion is the great sensory ganglion of CN V. It contains the sensory cell bodies of the 3 branches of the trigeminal nerve (the ophthalmic, mandibular, and maxillary divisions). (medscape.com)
Brainstem9
- Another area, not on the dorsum of the brainstem, is where the special visceral efferents nuclei reside. (wikipedia.org)
- Cranial nerve V, also known as the trigeminal nerve, originates from the pons, which is a part of the brainstem. (proprofs.com)
- 1, 2, 4, 9, 10 In mammals, all muscles involved in the oropharyngeal stage are striated and therefore are driven by several pools of motoneurons located mainly in various cranial motor nuclei in the brainstem. (nature.com)
- Other nuclei, however, are long and span several regions of the brainstem contributing to several cranial nerves. (radiopaedia.org)
- Several motor and sensory nuclei form longitudinal columns in the brainstem, leading to some authors describing them as single discontinuous longitudinal nuclear columns rather than the more numerous individual separate nuclei. (radiopaedia.org)
- Extensive interconnections exist between many of these nuclei, as well as with other brainstem nuclei and white matter tracts, such as the medial lemniscus and medial longitudinal fasciculus . (radiopaedia.org)
- The solitary nucleus (also called nucleus of the solitary tract , nucleus solitarius, or nucleus tractus solitarii (SN or NTS) ) [1] [2] is a series of sensory nuclei (clusters of nerve cell bodies) forming a vertical column of grey matter in the medulla oblongata of the brainstem. (wikipedia.org)
- The solitary nucleus projects to a large number of other regions of the brain including the paraventricular nucleus of the hypothalamus , the central nucleus of the amygdala , as well as other nuclei in the brainstem (such as the parabrachial area , locus coeruleus , dorsal raphe nucleus , and other visceral motor or respiratory networks). (wikipedia.org)
- The TCC also receives and makes projections to key areas of the brainstem involved in the processing of nociceptive information from the head, including the superior salivatory nucleus, the ventrolateral periaqueductal gray and rostral ventromedial medulla. (medscape.com)
Spinal cord3
- The sensory trigeminal nerve nuclei are the largest of the cranial nerve nuclei, and extend through the whole of the midbrain, pons and medulla, and into the high cervical spinal cord. (wikipedia.org)
- In animal models, it has been demonstrated that the central afferent projection to the trigeminal nucleus, using stimulation of the dura mater, also extends to the C2 and C3 regions of the cervical spinal cord, [ 9-13 ] which have been collectively described as the trigeminocervical complex (TCC). (medscape.com)
- [ 14 , 15 ] It is thought that the anatomical transition from the trigeminal nucleus to the cervical spinal cord represents a functional continuum and it is likely that inputs to the TCC can explain the common distribution of pain in migraine in frontal, temporal, parietal, occipital and higher cervical regions. (medscape.com)
Neurons13
- We have previously identified a projection from the jaw muscle afferent mesencephalic trigeminal nucleus (Vme) neurons to oculomotor nuclei (III/IV) and their premotor neurons in interstitial nucleus of Cajal (INC)-a well-known pre-oculomotor center manipulating vertical-torsional eye movements. (listlabs.com)
- Thus, we injected different anterograde tracers into the Vme and medial vestibular nucleus (MVN)-the subnuclear area particularly harboring excitatory vestibulo-ocular neurons, and immunostained III/IV motoneurons. (listlabs.com)
- Therefore, the convergent innervation of the Vme and MVN neurons onto the oculomotor and pre-oculomotor nuclei would be a neuroanatomic substrate for interaction of masticatory proprioception with the vestibulo-ocular signals upon the oculomotor system during vertical-torsional VOR. (listlabs.com)
- A cranial nerve nucleus is a collection of neurons (gray matter) in the brain stem that is associated with one or more of the cranial nerves. (wikipedia.org)
- In general, motor nuclei are closer to the front (ventral), and sensory nuclei and neurons are closer to the back (dorsal). (wikipedia.org)
- We observed scattered 5-HT 1D -IR neurons in the nodose ganglia, and there was sparse terminal immunoreactivity in the solitary nucleus. (jneurosci.org)
- Here we demonstrate that similar activity amplification occurs in mice, and that this is related to suppressed inhibition to PB neurons from the central nucleus of the amygdala (CeA) in animals of either sex. (iasp-pain.org)
- We describe a novel pathway, consisting of inhibition by dynorphin, somatostatin and corticotropin-releasing hormone expressing neurons in the central nucleus of the amygdala that project to the parabrachial nucleus (PB). (iasp-pain.org)
- [6] [7] Some neuronal subpopulations in the SN, such as the noradrenergic cell group A2 and the aldosterone -sensitive HSD2 neurons project as far ventral as the bed nucleus of the stria terminalis . (wikipedia.org)
- Here we tested the ability of graft-derived neurons to reestablish connectivity by forming neuronal relays between injured dorsal column (DC) sensory axons and the denervated dorsal column nuclei (DCN). (jneurosci.org)
- The jaw jerk reflex tests the integrity of the upper motor neurons projecting to the trigeminal motor nucleus. (standardofcare.com)
- Responses were compared with those in mice deficient in the cold/menthol receptor, TRPM8, expressed in trigeminal sensory neurons innervating the oral cavity. (bmj.com)
- Topographic Organization and Neurochemical Identity of Dorsal Raphe Neurons that Project to the Trigeminal Somatosensory Pathway in the Rat. (drexel.edu)
Afferent3
- Near the sulcus limitans are the visceral afferent nuclei, namely the solitary tract nucleus. (wikipedia.org)
- More lateral, but also less posterior, are the general somatic afferent nuclei. (wikipedia.org)
- The cranial nerve nuclei are a series of bilateral grey matter motor and sensory nuclei located in the midbrain , pons and medulla that are the collections of afferent and efferent cell bodies for many of the cranial nerves . (radiopaedia.org)
Divisions of the trigeminal nerve2
- Trigeminal neuralgia is a disorder characterized by recurrent unilateral brief electric shock-like pains, abrupt in onset and termination, limited to the distribution of one or more divisions of the trigeminal nerve. (radiologyassistant.nl)
- Pain due to trigeminal neuralgia occurs along the distribution of one or more sensory divisions of the trigeminal nerve, most often the maxillary. (msdmanuals.com)
Caudate nucleus1
- The scientists discovered differences in two connected brain regions-the caudate nucleus and the prefrontal cortex-that are involved in attention and impulse control. (medlineplus.gov)
Separate nuclei1
- The trigeminal nerve originates from two separate nuclei in the pons: the sensory division from the sensory nucleus (green dot) and the motor division from the motor nucleus (red dot). (radiologyassistant.nl)
Brain-stem4
- Photic sneeze reflex Trigeminal nerve Dissection of brain-stem. (wikipedia.org)
- Nitric oxide (NO) and cyclic GMP (cGMP) suppressed glutamatergic synaptic transmission to trigeminal motoneurons in brain stem slices of neonatal rats. (nih.gov)
- Nuclei of the trigeminal nerve situated in the brain stem. (nih.gov)
- Thus, neurologic deficits (usually loss of facial sensation) suggest that the trigeminal neuralgia-like pain is caused by another disorder (eg, tumor, stroke, multiple sclerosis plaque, vascular malformation, other lesions that compress the trigeminal nerve or disrupt its brain stem pathways). (msdmanuals.com)
Thalamic nuclei2
- Its axons cross to the other side, ascending to the thalamic nuclei to relay in the postcentral cerebral cortex. (medscape.com)
- Title : Simultaneous Top-down Modulation of the Primary Somatosensory Cortex and Thalamic Nuclei during Active Tactile Discrimination Personal Author(s) : Pais-Vieira, Miguel;Lebedev, Mikhail A.;Wiest, Michael C.;Nicolelis, Miguel A.L. (cdc.gov)
Cerebellum1
- Also expressed in trigeminal nucleus and small patches of cells in cerebellum. (brain-map.org)
Ambiguus1
- This area is a bit below the autonomic motor nuclei, and includes the nucleus ambiguus, facial nerve nucleus, as well as the motor part of the trigeminal nerve nucleus. (wikipedia.org)
Medulla oblongata1
- The nucleus solitarius is a series of purely sensory nuclei forming a vertical column of grey matter embedded within the medulla oblongata . (wikipedia.org)
Sensory nucleus6
- The sensory nucleus, located in the pons, is quite extensive. (medscape.com)
- The large rostral head is the main sensory nucleus. (medscape.com)
- The spinal tract is the sensory nucleus, primarily for pain and temperature. (medscape.com)
- The main sensory nucleus serves mostly for discrimination sense. (medscape.com)
- The motor nucleus is ventromedial to the sensory nucleus. (medscape.com)
- The sensory nucleus of CN V is connected to other motor nuclei of the pons and medulla. (medscape.com)
Efferent2
- Close to the midline are the motor efferent nuclei, such as the oculomotor nucleus, which control skeletal muscle. (wikipedia.org)
- Just lateral to this are the autonomic (or visceral) efferent nuclei. (wikipedia.org)
Trochlear nerve1
- All the nuclei except that of the trochlear nerve (CN IV) supply nerves of the same side of the body. (wikipedia.org)
Parabrachial1
- 2018 ) Amplified parabrachial nucleus activity in a rat model of trigeminal neuropathic pain. (neurotree.org)
Tractus solitarii1
- Nucleus tractus solitarii medullae oblongatae. (wikipedia.org)
Lesions2
- Lesions occurring at these nuclei can lead to effects resembling those seen by the severing of nerve(s) they are associated with. (wikipedia.org)
- Sensory loss starting from mouth and nose and extending concentrically outward observed in lesions of the trigeminal nucleus . (wikipedia.org)
Neuralgia6
- Several conditions may cause trigeminal neuralgia, but the most common cause is neurovascular compression. (radiologyassistant.nl)
- Trigeminal neuralgia is severe paroxysmal, lancinating facial pain due to a disorder of the 5th cranial nerve. (msdmanuals.com)
- Trigeminal neuralgia affects mainly adults, especially older people. (msdmanuals.com)
- Other disorders that cause similar symptoms (eg, multiple sclerosis) are sometimes considered to be trigeminal neuralgia and sometimes not. (msdmanuals.com)
- Symptoms of trigeminal neuralgia are often pathognomonic. (msdmanuals.com)
- Neurologic examination is normal in trigeminal neuralgia. (msdmanuals.com)
Nerve is the largest2
- The trigeminal nerve is the largest of all cranial nerves. (radiologyassistant.nl)
- The trigeminal nerve is the largest and most complex of the 12 cranial nerves (CNs). (medscape.com)
Tract1
- In the present study, the ABVN was targeted using PRF, which can alter the sensory nociceptors [ 9 ] and the electric stimulation switch on the Nucleus of the Solitary Tract (NTS) [ 10 ]. (tinnitusjournal.com)
Lateral1
- There is a separation, called the sulcus limitans, and lateral to this are the sensory nuclei. (wikipedia.org)
Axons1
- Axons carrying information to and from the cranial nerves form a synapse first at these nuclei. (wikipedia.org)
Ophthalmic1
- The ophthalmic division is in the lower part of the nucleus, and the mandibular branch is in the upper part. (medscape.com)
Motor4
- Histological studies showed guanylate cyclase (GC) containing fibers in the trigeminal motor pool. (nih.gov)
- Some nuclei are small and contribute to a single cranial nerve, such as some of the motor nuclei. (radiopaedia.org)
- This nucleus has connections to the motor nucleus of CN V. (medscape.com)
- The motor nucleus of CN V receives cortical fibers for voluntary control of the muscles of mastication. (medscape.com)
Facial1
- Apart from the major vagal nerve branch, spinal, trigeminal, and facial nerves run close to the ABVN innervation area [ 8 ]. (tinnitusjournal.com)
Pathways2
- Botox is injected into the V1, V2 and V3 pathways of the trigeminal nerve to specifically desensitise these neural pathways. (flexaclinic.com)
- One theory suggests that nerve compression causes local demyelination, which may result in ectopic impulse generation (ephaptic transmission) and/or disinhibition of central pain pathways involving the spinal trigeminal nucleus. (msdmanuals.com)
Motoneurons2
- Glutamatergic excitatory postsynaptic currents (EPSCs) were recorded from neonatal trigeminal motoneurons in response to stimulation of the supratrigeminal nucleus (SuV). (nih.gov)
- The results suggest that NO, through the synthesis of cGMP, presynaptically inhibits glutamatergic synaptic transmission on trigeminal motoneurons. (nih.gov)
Stimulation1
- Trigeminal nerve stimulation (TNS) is a noninvasive, non-drug treatment. (medlineplus.gov)