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Encyclopedia > Arcuate nucleus

The arcuate nucleus is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. The arcuate nucleus includes several important populations of neurons, including: Drawing by Santiago Ramón y Cajal of cells in the pigeon cerebellum. ... In the anatomy of mammals, the hypothalamus is a region of the brain located below the thalamus, forming the major portion of the ventral region of the diencephalon and functioning to regulate certain metabolic processes and other autonomic activities. ... The third ventricle is one of the four connected fluid-filled cavities within the human brain. ... Median Eminence The median eminence is part of the inferior boundary for the hypothalamus. ...

  • Neuroendocrine neurons with nerve endings in the median eminence, which release dopamine into the hypophysial portal blood. These are sometimes called the "tuberoinfundibular dopamine" (TIDA) neurons. In lactating females, TIDA neurons are inhibited by the stimulus of suckling. Dopamine released from their nerve endings at the median eminence is transported to the anterior pituitary gland, where it regulates the secretion of prolactin; dopamine inhibits prolactin secretion, so, when the TIDA neurons are inhibited, there is increased secretion of prolactin, which stimulates lactogenesis (milk production).
  • Neuroendocrine neurons, mainly in the ventrolateral part of the nucleus, that make growth hormone-releasing hormone (GHRH). Like the TIDA neurons, these neurons have nerve endings in the median eminence. GHRH released into the hypophysial portal blood is transported to the anterior pituitary gland, where it regulates the secretion of growth hormone; GHRH stimulates growth hormone secretion. These neurons are inhibited by somatostatin. The reciprocal relationship between the electrical activity of GHRH neurons and somatostatin neurons leads to pulsatile secretion of growth hormone, a pattern of secretion that is important for its biological effectiveness.
  • Centrally-projecting neurons that contain neuropeptide Y (NPY), agouti-related protein (AGRP), and the inhibitory neurotransmitter GABA. These neurons, in the most ventromedial part of the nucleus, project strongly to the lateral hypothalamus and to the paraventricular nucleus of the hypothalamus, and are important in the regulation of appetite. When activated, these neurons can produce ravenous eating. These neurons are regulated by circulating concentrations of leptin and ghrelin.
  • Centrally-projecting neurons that contain peptide products of pro-opiomelanocortin (POMC), and cocaine-and-amphetamine-regulating transcript (CART). These neurons have widespread projections to many brain areas, including to all nuclei in the hypothalamus. These cells are also important in the regulation of appetite, and, when activated, they inhibit feeding. These neurons are also regulated by circulating concentrations of leptin and ghrelin, and they are directly innervated by the NPY neurons. POMC neurons are also involved in the regulation of sexual behavior in both males and females.
  • Centrally-projecting neurons that make somatostatin; the neurosecretory somatostatin neurons that regulate growth hormone secretion are a different population, located in the periventricular nucleus.
  • A small population of neurons that synthesise ghrelin. The role of this population is not known; many neurons in the arcuate nucleus express receptors for ghrelin, but these are thought to be respond mainly to blood-borne ghrelin.

The arcuate nucleus also contains a population of specialized astrocytes, called tanycytes. Dopamine is a chemical naturally produced in the body. ... The anterior pituitary (also called the adenohypophysis) comprises the anterior lobe of the pituitary gland and is part of the endocrine system. ... Prolactin is a hormone synthesised and secreted by lactotrope cells in the adenohypophysis (anterior pituitary gland). ... Growth hormone-releasing hormone is a hormone released from the arcuate nucleus of hypothalamus that stimulates the release of growth hormone. ... Growth hormone Growth hormone is a polypeptide hormone synthesised and secreted by the anterior pituitary gland which stimulates growth and cell reproduction in humans and other vertebrate animals. ... Somatostatin is a hormone. ... Neuropeptide Y (NPY) is a 36 amino acid peptide neurotransmitter found in the brain and autonomic nervous system. ... Chemical structure of GABA Gamma-aminobutyric acid (GABA) is a neurotransmitter in widely divergent species. ... The paraventricular nucleus is a nucleus of mostly magnocellular neurosecretory cells in the hypothalamus, their axons extend into posterior pituitary. ... The appetite is the desire to eat food, felt as hunger. ... Leptin is a 16 kDa protein hormone that plays a key role in metabolism and regulation of adipose tissue. ... Ghrelin is a hormone that is produced by cells lining the stomach and stimulates the appetite. ... Peptides (from the Greek πεπτος, digestible), are the family of molecules formed from the linking, in a defined order, of various amino acids. ... Pro-opiomelanocortin (POMC) is a precursor polypeptide that is built of 241 amino acid residues. ... The appetite is the desire to eat food, felt as hunger. ... Leptin is a 16 kDa protein hormone that plays a key role in metabolism and regulation of adipose tissue. ... Ghrelin is a hormone that is produced by cells lining the stomach and stimulates the appetite. ... Sexual behavior is a form of physical intimacy that may be directed to reproduction (one possible goal of sexual intercourse) and/or to the enjoyment of activity involving sexual gratification. ... Ghrelin is a hormone that is produced by cells lining the stomach and stimulates the appetite. ... Astrocytes, also known as astroglia, are characteristic star-shaped cells in the brain. ...


References

Kawano H, Daikoku S 1988 Somatostatin-containing neuron systems in the hypothalamas: retrograde tracing and immunohistochemical studies. J Comp Neurol 271:293–299[Medline]



Prosencephalon (forebrain)

DIENCEPHALON: epithalamus (pineal body, habenula, habenular nuclei), third ventricle, thalamus (pulvinar, medial geniculate nucleus, lateral geniculate nucleus, thalamic reticular nucleus), hypothalamus (optic chiasm, arcuate nucleus, paraventricular nucleus, posterior nucleus, supraoptic nucleus, suprachiasmatic nucleus, ventromedial nucleus, infundibulum, mammillary body, median eminence), subthalamus (zona incerta), pituitary gland (anterior and posterior) In the anatomy of vertebrates, the prosencephalon is a part of encephalon, or brain. ... The diencephalon is the region of the brain that includes the epithalamus, thalamus, and hypothalamus. ... The epithalamus is a dorsal posterior segment of the diencephalon (a segment in the middle of the brain also containing the hypothalamus and the thalamus) which includes the habenula, the stria medullaris and the pineal body. ... The pineal gland (pronunciation: pI-nE-&l, pI-), or epiphysis, is a small endocrine gland located near the middle of the brain. ... This article may be too technical for most readers to understand. ... The habenular nuclei are a group of small nuclei which are part of the diencephalon. ... The third ventricle is one of the four connected fluid-filled cavities within the human brain. ... MRI cross-section of human brain, with thalamus marked. ... The pulvinar is the caudal-most nucleus of the thalamus that is conventionally divided into oral, inferior, lateral, and medial subnuclei. ... The medial geniculate nucleus is a nucleus of the thalamus that acts as a relay for auditory information. ... The lateral geniculate nucleus (LGN) of the thalamus is a part of the brain, which is the primary processor of visual information, received from the retina, in the CNS. Schematic diagram of the primate lateral geniculate nucleus. ... The thalamic reticular nucleus is part of the ventral thalamus that forms a capsule around the thalamus laterally. ... In the anatomy of mammals, the hypothalamus is a region of the brain located below the thalamus, forming the major portion of the ventral region of the diencephalon and functioning to regulate certain metabolic processes and other autonomic activities. ... Visual pathway with optic chiasm circled The optic chiasm (from the Greek χλαζειν to mark with an X, after the letter Χ chi) is the part of the brain where the optic nerves partially cross, those parts of the right eye which see things on the right side being connected to the... The paraventricular nucleus is a nucleus of mostly magnocellular neurosecretory cells in the hypothalamus, their axons extend into posterior pituitary. ... The posterior nucleus of the hypothalamus is one of the many nuclei that make up the hypothalamic region of the brain. ... In biology, the supraoptic nucleus is a nucleus of magnocellular neurosecretory cells in the hypothalamus, their axons extend into posterior pituitary. ... The suprachiasmatic nucleus (SCN) is a nucleus in the hypothalamus and is so named because it resides immediately above the optic chaism (OX). ... The ventromedial hypothalamus has two parts; The superior and anterior parts. ... An infundibulum is the latin for funnel and is a funnel-shaped cavity or organ. ... The mammillary bodies (Latin: corpus mamillare) are a pair of small round bodies in the brain forming part of the limbic system. ... Median Eminence The median eminence is part of the inferior boundary for the hypothalamus. ... The subthalamus, or ventral thalamus, is part of the diencephalon. ... The zona incerta is a small region of gray matter that is part of the subthalamus. ... Located at the base of the skull, the pituitary gland is protected by a bony structure called the sella turcica. ... The anterior pituitary (also called the adenohypophysis) comprises the anterior lobe of the pituitary gland and is part of the endocrine system. ... The posterior pituitary (also called the neurohypophysis) comprises the posterior lobe of the pituitary gland and is part of the endocrine system. ...


TELENCEPHALON: cerebral cortex, cerebral hemispheres, corona radiata, insular cortex, lateral sulcus, central sulcus, medial longitudinal fissure, primary sensory areas, fornicate gyrus The telencephalon (te-len-seff-a-lon) is the technical name for a large region within the brain which is attributed many functions, which some groups would class as unique features which make humans stand out from other species. ... Location of the cerebral cortex Slice of the cerebral cortex, ca. ... Human brain viewed from above, showing cerebral hemispheres. ... The corona radiata surround an ovum or unfertilized egg cell, and consist of two or three strata (layers) of follicular cells. ... The insular cortex (also often referred to as just the insula) is a structure of the human brain. ... Lateral sulcus The lateral sulcus (also called Sylvian fissure or lateral fissure) is one of the most prominent structures of the human brain. ... Central sulcus of the human brain. ... The medial longitudinal fissure is the deep groove which separates the two hemispheres of the vertebrate brain. ... The primary sensory areas are the main cerebral areas that receive sensory information from thalamic nerve projections. ... The Fornicate Gyrus is connected to the amydala, the mid region of the parietal region of the skull. ...


frontal lobe: primary motor cortex, prefrontal cortex, superior frontal gyrus, middle frontal gyrus, inferior frontal gyrus, Broca's area, Pars opercularis, orbitofrontal cortex, 4, 6, 8, 9, 10, 11, 24, 25, 32, 33, 44, 45, 46, 47 The frontal lobe is an area in the brain of vertebrates. ... The primary motor area is a group of networked cells in mammalian brains that controls movements of specific body parts associated with cell groups in that area of the brain. ... // Location and Function The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and associative areas. ... Superior frontal gyrus of the human brain. ... Middle frontal gyrus of the human brain. ... Inferior frontal gyrus of the human brain. ... Brocas area is the section of the human brain (in the opercular and triangular sections of the inferior frontal gyrus of the frontal lobe of the cortex) that is involved in language processing, speech production and comprehension. ... The Pars Opercularis is part of the inferior frontal gyrus and is part of the mirror neurons. ... The orbitofrontal cortex is a region of association cortex the human brain involved in cognitive processes such as decision making. ... Brodmann area 4 of human brain. ... Categories: Stub | Cerebrum ... // Human Brodmann area 8, or BA8, is part of the frontal cortex in the human brain. ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... 24 - ventral anterior cingulate (area cingularis anterior ventralis). ... // Human Brodmann area 25 (BA25) is an area in the cerebral cortex of the brain and delineated based on its cytoarchitectonic characteristics. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... This area is known as pregenual area 33, and it refers to a subdivision of the cytoarchitecturally defined cingulate region of cerebral cortex. ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... // Where is it? Brodmann area 46, or BA46, is part of the frontal cortex in the human brain. ... Where is it? Brodmann area 47, or BA47, is part of the frontal cortex in the human brain. ...


temporal lobe: primary somatosensory cortex, superior temporal gyrus, fusiform gyrus, parahippocampal gyrus, transverse temporal gyrus, Wernicke's area, 9, 20, 21, 22, 27, 34, 35, 36, 37, 38, 41, 42 The temporal lobes are part of the cerebrum. ... The postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... Superior temporal gyrus of the human brain. ... Please observe: the above picture was copied from this fantastic brain atlas The Fusiform gyrus is part of the temporal lobe. ... The parahippocampal gyrus is a grey matter cortical region of the brain that surrounds the hippocampus. ... The transverse temporal gyri (also called Heschls gyri) are found in the area of primary auditory cortex in the superior temporal gyrus of the human brain. ... Wernickes area is a part of the human brain that forms part of the cortex, on the left posterior section of the superior temporal gyrus, posterior to the primary auditory cortex, on the temporo-parietal junction (part of the brain where the temporal lobe and parietal lobe meet). ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... On the left side of the brain is an area called Brodmann’s area 22, that help generate and help the understanding of individual words, and on the right side of the brain it helps tell the difference between melody, pitch, and sound intensity. ... The term area 27 of Brodmann-1909 refers to a cytoarchitecturally defined cortical area that is a rostral part of the PARAHIPPOCAMPAL GYRUS of the guenon (Brodmann-1909). ... You have new messages. ... // Human This area is known as perirhinal area 35, and it refers to a subdivision of the cytoarchitecturally defined hippocampal region of the cerebral cortex. ... This area is known as ectorhinal area 36, and it refers to a subdivision of the cytoarchitecturally defined temporal region of cerebral cortex. ... Categories: Stub | Cerebrum ... Categories: Stub | Cerebrum ... The primary auditory cortex the region of the brain which is responsible for processing of auditory (sound) information. ... The primary auditory cortex the region of the brain which is responsible for processing of auditory (sound) information. ...


parietal lobe: primary auditory cortex, postcentral gyrus, precuneus, postcentral sulcus, 1, 2, 3, 5, 7, 23, 26, 29, 31, 39, 40 The parietal lobe is a lobe in the brain. ... The primary auditory cortex the region of the brain which is responsible for processing of auditory (sound) information. ... The lateral postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... The precuneus is a structure in the brain positioned above the cuneus and located in the parietal lobe. ... Postcentral sulcus of the human brain. ... The postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... The postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... The postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... Brodmann area 5 is part of the parietal cortex in the human brain. ... Categories: Stub | Cerebrum ... Brodmann area 23 (BA23) is a region in the brain corresponding to some portion of the posterior cingulate cortex. ... This article may be too technical for most readers to understand. ... This area is known as granular retrolimbic area 29, and it refers to a cytoarchitecturally defined portion of the retrosplenial region of the cerebral cortex. ... This area is known as dorsal posterior cingulate area 31, and it refers to a subdivision of the cytoarchitecturally defined cingulate region of cerebral cortex. ... Categories: Stub | Cerebrum ... Brodmann area 40, or BA40, is part of the parietal cortex in the human brain. ...


occipital lobe: primary visual cortex, cuneus, 23, 24; 26, 29, 30, 31, 32 The occipital lobe is the visual processing center of the mammalian brain. ... Brodmann area 17 (primary visual cortex) is shown in red in this image which also shows area 18 (orange) and 19 (yellow) The primary visual cortex (usually called V1) is the most well-studied visual area in the brain. ... Cuneus (Latin for wedge; plural, cunei), the architectural term applied to the wedge-shaped divisions of the Roman theatre separated by the scalae or stairways; see Vitruvius v. ... Brodmann area 23 (BA23) is a region in the brain corresponding to some portion of the posterior cingulate cortex. ... 24 - ventral anterior cingulate (area cingularis anterior ventralis). ... This article may be too technical for most readers to understand. ... This area is known as granular retrolimbic area 29, and it refers to a cytoarchitecturally defined portion of the retrosplenial region of the cerebral cortex. ... This area is known as agranular retrolimbic area 30, and it refers to a subdivision of the cytoarchitecturally defined retrosplenial region of the cerebral cortex. ... This area is known as dorsal posterior cingulate area 31, and it refers to a subdivision of the cytoarchitecturally defined cingulate region of cerebral cortex. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...


cingulate cortex: anterior cingulate, cingulate gyrus, cingulate sulcus, 23, 24; 26, 29, 30, 31, 32 The cingulate cortex is part of the brain and situated roughly in the middle of the cortex. ... Anterior cingulate cortex (ACC) is the frontal part of the cingulate cortex and includes Brodmanns area 24 (ventral ACC) and 32 (dorsal ACC). ... Cingulate gyrus is a gyrus in the medial part of the brain. ... Categories: Stub | Cerebrum ... Brodmann area 23 (BA23) is a region in the brain corresponding to some portion of the posterior cingulate cortex. ... 24 - ventral anterior cingulate (area cingularis anterior ventralis). ... This article may be too technical for most readers to understand. ... This area is known as granular retrolimbic area 29, and it refers to a cytoarchitecturally defined portion of the retrosplenial region of the cerebral cortex. ... This area is known as agranular retrolimbic area 30, and it refers to a subdivision of the cytoarchitecturally defined retrosplenial region of the cerebral cortex. ... This area is known as dorsal posterior cingulate area 31, and it refers to a subdivision of the cytoarchitecturally defined cingulate region of cerebral cortex. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...


subcortical: amygdala, hippocampus (dentate gyrus, cornu ammonis), basal ganglia (globus pallidus, striatum, caudate nucleus, putamen), claustrum, rhinencephalon, olfactory bulb, piriform cortex, lateral ventricles Location of the amygdala in the human brain Located deep in the brains medial temporal lobe, the almond-shaped amygdala (in Latin, corpus amygdaloideum) is believed to play a key role in the emotions. ... The location of the hippocampus in the human brain. ... The dentate gyrus is part of the hippocampal formation. ... Daigram of hippocampal regions. ... The basal ganglia are a group of nuclei in the brain associated with motor and learning functions. ... The globus pallidus (Latin for pale body) is a sub-cortical structure in the brain. ... The striatum is a subcortical part of the brain consisting of the caudate nucleus and the putamen. ... The caudate nucleus is a telencephalic nucleus, one of the input nuclei of the basal ganglia; involved with control of voluntary movement in the brain. ... The putamen is a structure in the middle of the brain, forming the striatum together with the caudate nucleus. ... The claustrum is a thin layer of grey matter lying between the extreme capsule and external capsule in the brain. ... In anatomy of animals, the rhinencephalon is a part of the brain involved with olfaction. ... The olfactory bulb (1) is relatively large in the rabbit brain The olfactory bulb is a part of the brain that is a distinct outgrowth from the forebrain of mammals. ... In anatomy of animals, the piriform cortex, or pyriform cortex is a region in the brain. ... The ventricular system is a fluid conducting system within the brain. ...


NEURAL PATHWAYS: arcuate fasciculus, corpus callosum, corticospinal tract, dopamine pathways (mesocortical, mesolimbic, nigrostriatal, tuberoinfundibular), capsules (external, extreme, internal) A neural pathway is a neural tract connecting one part of the nervous system with another, usually consisting of bundles of elongated, myelin insultated neurons, known collectively as white matter. ... Figure one illustrates significant language areas of the brain. ... Grays FIG. 733– Corpus callosum from above. ... The corticospinal or pyramidal tract is a massive collection of axons that travel between the cerebral cortex of the brain, and the spinal cord. ... The mesocortical pathway is a neural pathway which connects the ventral tegmentum to the cortex, particularly the frontal lobes. ... The mesolimbic pathway is one of the neural pathways in the brain which links the ventral tegmentum area in the midbrain to the nucleus accumbens in the limbic system. ... The nigrostriatal pathway is a neural pathway which connects the substantia nigra with the striatum. ... The tuberoinfundibular pathway is a neural pathway which runs between the hypothalamus and the pituitary gland. ... The external capsule is a series of white matter fiber tracts in the brain. ... The extremem capsule is a series of white matter fiber tracts in the brain. ... The internal capsule is an area of white matter in the brain that separates the caudate nucleus and the thalamus from the lenticular nucleus. ...


  Results from FactBites:
 
Nucleus (neuroanatomy) - Wikipedia, the free encyclopedia (170 words)
In neuroanatomy, a nucleus is a central nervous system structure that is composed mainly of gray matter, and which acts as a hub or transit point for electrical signals in a single neural subsystem.
Other examples include the Raphe nucleus, which is involved in sleep, and the suprachiasmatic nucleus, which controls circadian rhythm.
All the nerve cell axons terminating on a nucleus tend to employ the same neurotransmitter at their synapses.
Angiotensin II AT1A Receptor mRNA Expression Is Induced by Estrogen-Progesterone in Dopaminergic Neurons of the Female ... (5368 words)
Colocalization of AT receptor mRNA with tyrosine hydroxylase in the arcuate nucleus
in neurons of the arcuate nucleus of estrogen/progesterone-treated
and tyrosine hydroxylase immunoreactivity in neurons of the arcuate
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