In which organ of the body is the pineal gland?
"the central nervous system and particularly of the pineal region are very rare and so diagnosing them is extremely difficult. Pineal region tumors are normally composed of a variety of cells including astrocytes, ganglion cells, blood vessels, and pinealocytes, which are the cells of this organ. Pinealocytes are specialized neurons, which are rich in monoaminergic neurotransmitters, including, serotonin, norepinephrine, and melatonin. Specifically, papillary tumors of this region are made up of ependymal cells which form papilla. The papilla is meant to be surface cells. The ependymal cells line the inside of the ventricles of the brain. These cells have proteins"
"gland in different vertebrate species. From the point of view of biological evolution, the pineal gland represents a kind of atrophied photoreceptor. In the epithalamus of some species of amphibians and reptiles, it is linked to a light-sensing organ, known as the parietal eye, which is also called the pineal eye or ""third eye"". René Descartes believed the human pineal gland to be the ""principal seat of the soul"". Academic philosophy among his contemporaries considered the pineal gland as a neuroanatomical structure without special metaphysical qualities; science studied it as one endocrine gland among many. The word ""pineal"", from Latin"
"a ""mystery"" gland with mystical, metaphysical, and occult theories surrounding its perceived functions. The pineal gland was originally believed to be a ""vestigial remnant"" of a larger organ. In 1917, it was known that extract of cow pineals lightened frog skin. Dermatology professor Aaron B. Lerner and colleagues at Yale University, hoping that a substance from the pineal might be useful in treating skin diseases, isolated and named the hormone melatonin in 1958. The substance did not prove to be helpful as intended, but its discovery helped solve several mysteries such as why removing the rat's pineal accelerated ovary growth,"
"subsequently fuses into a single pineal gland in developing embryos of turtles, snakes, birds, and mammals. The pineal organs of mammals fall into one of three categories based on shape. Rodents have more structurally-complex pineal glands than other mammals. Crocodilians and some tropical lineages of mammals (some xenarthrans [sloths], pangolins, sirenians [manatees & dugongs], and some marsupials [sugar gliders]) have lost both their parietal eye and their pineal organ. Polar mammals, such as walruses and some seals, possess unusually large pineal glands. All amphibians have a pineal organ, but some frogs and toads also have what is called a ""frontal"
"the pineal gland, and the habenular commissure. It is wired with the limbic system and basal ganglia. Species that possess a photoreceptive parapineal organ show asymmetry in the epithalamus at the habenula, to the left (dorsal). Epithalamus The epithalamus is a (dorsal) posterior segment of the diencephalon. The diencephalon is a part of the forebrain that also contains the thalamus, the hypothalamus and pituitary gland. The epithalamus includes the habenula and their interconnecting fibers, the habenular commissure, the stria medullaris and the pineal gland. The function of the epithalamus is to connect the limbic system to other parts of the"
"Pituitary gland In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The hypophysis rests upon the hypophysial fossa of the sphenoid bone in the center of the middle cranial fossa and is surrounded by a small bony cavity (sella turcica) covered by a dural fold (diaphragma sellae). The anterior pituitary (or adenohypophysis) is a lobe of the gland that regulates several physiological processes (including stress, growth, reproduction, and lactation). The intermediate"
"through the circulatory system and by direct connection of neurons. Also, within the cranium, the pineal gland, which attaches to the thalamus, controls the body's 24-hour rhythms circadian rhythm through the release of melatonin. The pituitary gland secretes hormones that directly impact the body as well as hormones that indirectly control body functions because they activate other endocrine glands, such as the adrenal cortex (ACTH) and the thyroid gland (TSH). These two glands when stimulated by pituitary hormones then release their own hormones. The pituitary gland has two lobes, the anterior lobe and the posterior lobe. The anterior lobe secretes:"
"Pinealocyte Pinealocytes are the main cells contained in the pineal gland, located behind the third ventricle and between the two hemispheres of the brain. The primary function of the pinealocytes is the secretion of the hormone melatonin, important in the regulation of circadian rhythms. In humans, the suprachiasmatic nucleus of the hypothalamus communicates the message of darkness to the pinealocytes, and as a result, controls the day and night cycle. It has been suggested that pinealocytes are derived from photoreceptor cells. Research has also shown the decline in the number of pinealocytes by way of apoptosis as the age of"
"Epithalamus The epithalamus is a (dorsal) posterior segment of the diencephalon. The diencephalon is a part of the forebrain that also contains the thalamus, the hypothalamus and pituitary gland. The epithalamus includes the habenula and their interconnecting fibers, the habenular commissure, the stria medullaris and the pineal gland. The function of the epithalamus is to connect the limbic system to other parts of the brain. Some functions of its components include the secretion of melatonin and secretion of hormones from pituitary gland by the pineal glandcircadian rhythms), and regulation of motor pathways and emotions. The epithalamus comprises the habenular trigone,"
"Pancreas The pancreas is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdominal cavity behind the stomach. The pancreas is a mixed gland, having both an endocrine and an exocrine function. As an endocrine gland, it secretes into the blood several important hormones, including insulin, glucagon, somatostatin, and pancreatic polypeptide. As an exocrine gland, it secretes pancreatic juice into the duodenum through the pancreatic duct. This juice contains bicarbonate, which neutralizes acid entering the duodenum from the stomach; and digestive enzymes, which break down carbohydrates, proteins, and lipids in ingested"
"Anterior pituitary A major organ of the endocrine system, the anterior pituitary (also called the adenohypophysis or pars anterior), is the glandular, anterior lobe that together with the posterior lobe (posterior pituitary, or the neurohypophysis) makes up the pituitary gland (hypophysis). The anterior pituitary regulates several physiological processes including stress, growth, reproduction and lactation. Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels. The pituitary gland is a pea-sized gland that sits in a protective bony enclosure called the sella turcica (""Turkish chair/saddle""). It is composed"
"they are diagnosed. The pons in the brainstem is a specific region that consists of myelinated axons much like the spinal cord. The thalamus and hypothalamus of the diencephalon also consist of neuron and glial cell tissue with the hypophysis (pituitary gland) and pineal gland (which is glandular tissue) attached at the bottom; tumors of the pituitary and pineal gland are often benign. The medulla oblongata is at the start of the spinal cord and is composed mainly of neuron tissue enveloped in oligodendrocytes and meninges tissue. The spinal cord is made up of bundles of these axons. Glial cells"
"doesn’t supply it with much innervation. The most important set of fibers involved are the unmyelinated postganglionic sympathetic fibers from the superior cervical ganglia (SCG), which also form the bilateral nervi conarii. The second set of fibers enters the pineal gland anteriorly via the commissural peduncles. The third set of fibers is myelinated and forms the ventro-lateral pineal tract. The pineal gland is considered a secretory organ and its activity shows circadian oscillations. Its main function, secretion of the hormone melatonin, dies out when there is no input from the primary circadian pacemaker in the suprachiasmatic nuclei (SCN). Melatonin production"
"increase in the concentration of FSH and LH within the gland. Administration of melatonin did not return the concentrations of FSH to normal levels, suggesting that the pineal gland influences pituitary gland secretion of FSH and LH through an undescribed transmitting molecule. The pineal gland contains receptors for the regulatory neuropeptide, endothelin-1, which, when injected in picomolar quantities into the lateral cerebral ventricle, causes a calcium-mediated increase in pineal glucose metabolism. Studies on rodents suggest that the pineal gland may influence the actions of recreational drugs, such as cocaine, and antidepressants, such as fluoxetine (Prozac), and that its hormone melatonin"
"gland is located at the base of the brain, and intimately connected with the hypothalamus. It consists of two lobes: the posterior pituitary, which consists of nervous tissue branching out of the hypothalamus, and the anterior pituitary, which consists of hormone-producing epithelium. The posterior pituitary secretes antidiuretic hormone, which regulates osmolarity of the blood, and oxytocin, which causes contractions of the uterus in childbirth and participates in breastfeeding. The pituitary develops in the third week of embryogenesis from interactions between the diencephalon part of the brain and the nasal cavity. The brain cells secrete FGF-8, Wnt5a and BMP-4, and the"
"the culinary name of sweetbread. Pancreas The pancreas is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdominal cavity behind the stomach. The pancreas is a mixed gland, having both an endocrine and an exocrine function. As an endocrine gland, it secretes into the blood several important hormones, including insulin, glucagon, somatostatin, and pancreatic polypeptide. As an exocrine gland, it secretes pancreatic juice into the duodenum through the pancreatic duct. This juice contains bicarbonate, which neutralizes acid entering the duodenum from the stomach; and digestive enzymes, which break down carbohydrates,"
"Nerve fibers then relay the daylight information from the SCN to the paraventricular nuclei (PVN), then to the spinal cord and via the sympathetic system to superior cervical ganglia (SCG), and from there into the pineal gland. The compound pinoline is also claimed to be produced in the pineal gland; it is one of the beta-carbolines. This claim is subject to some controversy. Studies on rodents suggest that the pineal gland influences the pituitary gland's secretion of the sex hormones, follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Pinealectomy performed on rodents produced no change in pituitary weight, but caused an"
"Habenula In neuroanatomy, habenula (diminutive of Latin ""habena"" meaning rein) originally denoted the stalk of the pineal gland (pineal habenula; pedunculus of pineal body), but gradually came to refer to a neighboring group of nerve cells with which the pineal gland was believed to be associated, the habenular nucleus. The habenular nucleus is a set of well-conserved structures in all vertebrate animals. Currently, the Terminologia Anatomica term refers exclusively to this separate cell mass in the caudal and dorsal aspect of the dorsal thalamus (the epithalamus), embedded in the posterior end of the medullary stria from which it receives most"
"lobe synthesizes and secretes melanocyte-stimulating hormone. The posterior pituitary (or neurohypophysis) is a lobe of the gland that is functionally connected to the hypothalamus by the median eminence via a small tube called the pituitary stalk (also called the infundibular stalk or the infundibulum). Hormones secreted from the pituitary gland help in controlling growth, blood pressure, energy management, all functions of the sex organs, thyroid glands and metabolism as well as some aspects of pregnancy, childbirth, nursing, water/salt concentration at the kidneys, temperature regulation and pain relief. The pituitary gland, in humans, is a pea-sized gland that sits in a"
"important to many animals. For instance, in fish, it is believed to control physiological color change. In adult humans, it is just a thin layer of cells between the anterior and posterior pituitary. The intermediate lobe produces melanocyte-stimulating hormone (MSH), although this function is often (imprecisely) attributed to the anterior pituitary. The intermediate lobe is, in general, not well developed in tetrapods, and is entirely absent in birds. Pituitary gland In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing in humans. It is a protrusion off the bottom of"
"or pineal gland if mostly endocrine) and the parietal organ (often called the parietal eye, or third eye if it is photoreceptive). It arises as an anterior evagination of the pineal organ or as a separate outgrowth of the roof of the diencephalon. In some species, it protrudes through the skull. The parietal eye uses a different biochemical method of detecting light from that of rod cells or cone cells in a normal vertebrate eye. Many of the oldest fossil vertebrates, including ostracoderms, placoderms, crossopterygians, and even early tetrapods, had a socket in the skull that appears to have held"
"made up of small lobes and a cortex that possesses a diffuse distribution of neurons. The principal cell type of the pineal is the pinealocyte sensu stricto. This type of cell has a prominent nucleus and a granular appearance. The level of vascularization in the pineal gland is high. It receives a large supply of blood from branches of the posterior choroidal arteries that derive from cerebral arteries in the posterior mesencephalon. The pineal gland is innervated by fibers from the peripheral parasympathetic and sympathetic systems, in addition to fibers from the central nervous system (CNS). However, the brain itself"
"""krīnō"", ""to separate, distinguish"". The human endocrine system consists of several systems that operate via feedback loops. Several important feedback systems are mediated via the hypothalamus and pituitary. Endocrine glands are glands of the endocrine system that secrete their products, hormones, directly into interstitial spaces and then absorbed into blood rather than through a duct. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands. The hypothalamus and pituitary gland are neuroendocrine organs. There are many types of cells that comprise the endocrine system and these"
"from Melovatka, about 90 million years old, shows a relatively large parietal eye and pineal gland. Seventeenth-century philosopher and scientist René Descartes was highly interested in anatomy and physiology. He discussed the pineal gland both in his first book, the ""Treatise of Man"" (written before 1637, but only published posthumously 1662/1664), and in his last book, ""The Passions of the Soul"" (1649) and he regarded it as ""the principal seat of the soul and the place in which all our thoughts are formed."" In the ""Treatise of Man"", Descartes described conceptual models of man, namely creatures created by God, which"
"is also known as the adenohypophysis, meaning ""glandular undergrowth"", from the Greek ""adeno-"" (""gland""), ""hypo"" (""under""), and ""physis"" (""growth""). Anterior pituitary A major organ of the endocrine system, the anterior pituitary (also called the adenohypophysis or pars anterior), is the glandular, anterior lobe that together with the posterior lobe (posterior pituitary, or the neurohypophysis) makes up the pituitary gland (hypophysis). The anterior pituitary regulates several physiological processes including stress, growth, reproduction and lactation. Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels. The pituitary gland is"
"gland. The postganglionic axons of the SCG innervate the pineal gland and are involved in Circadian rhythm. This connection regulates production of the hormone melatonin, which regulates sleep and wake cycles, however the influence of SCG neuron innervation of the pineal gland is not fully understood. The postganglionic axons of the SCG innervate the internal carotid artery and form the internal carotid plexus. The internal carotid plexus carries the postganglionic axons of the SCG to the eye, lacrimal gland, mucous membranes of the mouth, nose, and pharynx, and numerous blood-vessels in the head. The postganglionic axons of the SCG innervate"
"functionally connected to the brain, the pituitary gland sits outside the blood–brain barrier. It is separated from the subarachnoid space by the diaphragma sella, therefore the arachnoid mater and thus cerebral spinal fluid cannot enter the sella turcica. The pituitary gland is divided into two lobes, the anterior lobe (which accounts for two thirds of the volume of the gland), and the posterior lobe (one third of the volume) separated by the pars intermedia. The posterior lobe (the neural lobe or neurohypophysis) of the pituitary gland is not, despite its name, a true gland. The posterior lobe contains axons of"
"maintain their own rhythm in the absence of external cues. The SCN takes the information on the lengths of the day and night from the retina, interprets it, and passes it on to the pineal gland, a tiny structure shaped like a pine cone and located on the epithalamus. In response, the pineal secretes the hormone melatonin.Secretion of melatonin peaks at night and ebbs during the day and its presence provides information about night-length. Several studies have indicated that pineal melatonin feeds back on SCN rhythmicity to modulate circadian patterns of activity and other processes. However, the nature and system-level"
"seal between the third ventricle and the median eminence. This seal can be attributed to the tight junctions observed between tanycytes and functions to restrict the travel of molecules between the median eminence and the third ventricle. The median eminence is also closely linked to the transport of GnRH between the median eminence and the anterior pituitary. Neuronal projections of GnRH neurons actually end at the median eminence, allowing for its release into the portal blood system. The morphology of the pineal gland varies greatly among mammals. The most commonly used classification for this gland takes into account its location"
"gland in the digestive system. It is both an endocrine gland and an exocrine gland. The endocrine part secretes insulin when the blood sugar becomes high; insulin moves glucose from the blood into the muscles and other tissues for use as energy. The endocrine part releases glucagon when the blood sugar is low; glucagon allows stored sugar to be broken down into glucose by the liver in order to re-balance the sugar levels. The pancreas produces and releases important digestive enzymes in the pancreatic juice that it delivers to the duodenum. The pancreas lies below and at the back of"
"that directly extend from cell bodies in the hypothalamus, through the infundibulum. It is located in the sella turcica of the sphenoid bone at the base of the skull. The pituitary is sometimes referred to as the “master gland” because it has a crucial role in maintaining homeostasis and guiding the activity of other glands. The anterior lobe secretes growth hormone, prolactin and tropic hormones for the thyroid, gonads and adrenal glands. The posterior lobe stores and releases oxytocin and vasopressin, also known as antidiuretic hormone (ADH), which are produced in the hypothalamus. The median eminence (ME) is located in"
"distalis (pars glandularis) that constitutes ~80% of the gland. The pars intermedia (the intermediate lobe) lies between the pars distalis and the pars tuberalis, and is rudimentary in the human, although in other species it is more developed. It develops from a depression in the dorsal wall of the pharynx (stomal part) known as Rathke's pouch. The anterior pituitary contains several different types of cells that synthesize and secrete hormones. Usually there is one type of cell for each major hormone formed in anterior pituitary. With special stains attached to high-affinity antibodies that bind with distinctive hormone, at least 5"
"a constitutional duplication of a chromosome Xq26.3 including ""GPR101"", or mosaicism for the duplication (present in a minority of cells) in the case of isolated male patients. X-LAG causes about 10% of cases of pituitary gigantism. The pituitary gland or hypophysis is often referred to as the ""master gland"" of the human body. Part of the hypothalamic-pituitary axis, it controls most of the body's endocrine functions via the secretion of various hormones into the circulatory system. The pituitary gland is located below the brain in a depression (fossa) of the sphenoid bone known as the sella turcica. Although anatomically and"