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Hypogonadotrophic Hypogonadism
Hypogonadotropic hypogonadism (HH), is due to problems with either the hypothalamus or pituitary gland affecting the hypothalamic-pituitary-gonadal axis (HPG axis). Hypothalamic disorders result from a deficiency in the release of gonadotropic releasing hormone (GnRH), while pituitary gland disorders are due to a deficiency in the release of gonadotropins from the anterior pituitary. GnRH is the central regulator in reproductive function and sexual development via the HPG axis. GnRH is released by GnRH neurons, which are hypothalamic neuroendocrine cells, into the hypophyseal portal system acting on gonadotrophs in the anterior pituitary. The release of gonadotropins, LH and FSH, act on the gonads for the development and maintenance of proper adult reproductive physiology. LH acts on Leydig cells in the male testes and theca cells in the female. FSH acts on Sertoli cells in the male and follicular cells in the female. Combined this causes the secretion of gonadal sex steroi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothalamus
The hypothalamus (: hypothalami; ) is a small part of the vertebrate brain that contains a number of nucleus (neuroanatomy), nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamus is located below the thalamus and is part of the limbic system. It forms the Basal (anatomy), basal part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is about the size of an Almond#Nut, almond. The hypothalamus has the function of regulating certain metabolic biological process, processes and other activities of the autonomic nervous system. It biosynthesis, synthesizes and secretes certain neurohormones, called releasing hormones or hypothalamic hormones, and these in turn stimulate or inhibit the secretion of hormones from the pituitary gland. The hypothalamus controls thermoregulation, body temperature, hunger (physiology), hunger, important aspects o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kisspeptin
Kisspeptins (including kisspeptin-54 (KP-54), formerly known as metastin) are proteins encoded by the ''KISS1'' gene in humans. Kisspeptins are ligands of the G-protein coupled receptor, GPR54. ''Kiss1'' was originally identified as a human metastasis suppressor gene that has the ability to suppress melanoma and breast cancer metastasis. Kisspeptin-GPR54 signaling has an important role in initiating secretion of gonadotropin-releasing hormone (GnRH) at puberty, the extent of which is an area of ongoing research. Gonadotropin-releasing hormone is released from the hypothalamus to act on the anterior pituitary triggering the release of luteinizing hormone (LH), and follicle stimulating hormone (FSH). These gonadotropic hormones lead to sexual maturation and gametogenesis. Disrupting GPR54 signaling can cause hypogonadotrophic hypogonadism in rodents and humans. The Kiss1 gene is located on chromosome 1. It is transcribed in the brain, adrenal gland, liver, gonads, and pancreas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craniopharyngiomas
A craniopharyngioma is a rare type of brain tumor derived from pituitary gland embryonic tissue that occurs most commonly in children, but also affects adults. It may present at any age, even in the prenatal and neonatal periods, but peak incidence rates are childhood-onset at 5–14 years and adult-onset at 50–74 years. People may present with bitemporal inferior quadrantanopia leading to bitemporal hemianopsia, as the tumor may compress the optic chiasm. It has a point prevalence around two per 1,000,000. Craniopharyngiomas are distinct from Rathke's cleft tumours and intrasellar arachnoid cysts. Symptoms and signs Craniopharyngiomas are almost always benign. However, as with many brain tumors, their treatment can be difficult, and significant morbidities are associated with both the tumor and treatment. * Headache (obstructive hydrocephalus) * Hypersomnia * Myxedema * Postsurgical weight gain ( hypothalamic obesity) * Polydipsia * Polyuria (diabetes insipidus) * Vision ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pituitary Adenomas
Pituitary adenomas are tumors that occur in the pituitary gland. Most pituitary tumors are benign, approximately 35% are invasive and just 0.1% to 0.2% are carcinomas.Pituitary Tumors Treatment (PDQ®)–Health Professional Version NIH National Cancer Institute Pituitary adenomas represent from 10% to 25% of all intracranial , with an estimated in the general population of approximately 17%. Non-invasive and non-secreting pituitary adenomas are considered to be [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphocytic Hypophysitis
Autoimmune hypophysitis is defined as inflammation of the pituitary gland due to autoimmunity. Signs and symptoms Autoimmune hypophysitis can lead to deficiencies in one or more pituitary hormones, causing central diabetes insipidus if the posterior pituitary gland is affected as well as central adrenal insufficiency and central hypothyroidism if the anterior pituitary gland is affected. The symptoms depend on what part of the pituitary is affected. Lymphocytic adenohypophysitis (LAH) occurs when the anterior pituitary cells are affected by autoimmune inflammation resulting in either no symptoms, adrenal insufficiency (if the ACTH producing cells are affected), hypothyroidism (if the TSH producing cells are damaged), or hypogonadism (if the LH and/or FSH producing cells are involved). In some cases, the presence of inflammation within the pituitary gland leads to interruption of dopamine flow from the hypothalamus into the pituitary causing high levels of the hormone prolactin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcoidosis
Sarcoidosis (; also known as Besnier–Boeck–Schaumann disease) is a disease involving abnormal collections of White blood cell, inflammatory cells that form lumps known as granulomata. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly affected are the eyes, liver, heart, and Human brain, brain, though any Organ (anatomy), organ can be affected. The signs and symptoms depend on the organ involved. Often, no symptoms or only mild symptoms are seen. When it affects the lungs, wheezing, coughing, shortness of breath, or chest pain may occur. Some may have Löfgren syndrome with fever, Bilateral hilar lymphadenopathy, enlarged hilar lymph nodes, arthritis, and a rash known as erythema nodosum. The cause of sarcoidosis is unknown. Some believe it may be due to an immune reaction to a trigger such as an infection or chemicals in those who are genetically predisposed. Those with affected family members are at greater risk. Diagnosis is partly based on signs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anosmin-1
Anosmin-1 is a secreted, EM associated glycoprotein found in humans and other organisms responsible for normal development, which is expressed in the brain, spinal cord and kidney. Absence or damage to the protein results in Kallmann syndrome in humans, which is characterized by loss of olfactory bulbs and GnRH secretion leading to anosmia and hypothalamic hypogonadotropic hypogonadism. Anosmin-1 is coded by the KAL-1 gene, which is found on the X chromosome. Anosmin-1 is 100 kilodaltons and is expressed on the outside of cells. Because of this and because of its contribution to normal migration of nerve cells, a role in the extracellular matrix has been postulated. Function During neural crest cell development, anosmin-1 plays a role in cranial neural cell formation by spatiotemporal regulation. Secreated anosmin-1 enhances FGF activity by promoting FGF8-FGFR1 complex formation, whereas inhibits both BMP5 and WNT3A activities. As a results, orchestrated regulation of FGF, BMP, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KISS1R
The KiSS1-derived peptide receptor (also known as GPR54 or the Kisspeptin receptor) is a G protein-coupled receptor which binds the peptide hormone kisspeptin (metastin). Kisspeptin is encoded by the metastasis suppressor gene KISS1, which is expressed in a variety of endocrine and gonadal tissues. Activation of the kisspeptin receptor is linked to the phospholipase C and inositol trisphosphate second messenger cascades inside the cell. Kisspeptins are neuropeptides synthesized in the hypothalamus and encoded by the KISS1 gene. The KISS1 gene encodes the G protein-coupled receptor 54 (known as KISS1R or GPR54) and plays a crucial role in regulating reproduction, pubertal maturation, and metabolic function. KISS1 neurons located in the arcuate nucleus (ARC) of the mediobasal hypothalamus (MBH) project to GnRH neurons in the median eminence, which expresses KISS1R, to stimulate LH secretions in a pulsatile manner from the anterior pituitary to initiate ovulation/ pubertal matura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNRH1
Gonadotropin-releasing hormone (GnRH) is a releasing hormone responsible for the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary. GnRH is a tropic peptide hormone synthesized and released from GnRH neurons within the hypothalamus. GnRH is inhibited by testosterone. The peptide belongs to gonadotropin-releasing hormone family. It constitutes the initial step in the hypothalamic–pituitary–gonadal axis. Structure The identity of GnRH was clarified by the 1977 Nobel Laureates Roger Guillemin and Andrew V. Schally: pyroGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2 As is standard for peptide representation, the sequence is given from amino terminus to carboxyl terminus; also standard is omission of the designation of chirality, with assumption that all amino acids are in their L- form. The abbreviations are the standard abbreviations for the corresponding proteinogenic amino acids, except for ''pyroGlu'', which refers to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNRHR
Gonadotropin-releasing hormone receptor is a protein that in humans is encoded by the ''GNRHR'' gene. This gene encodes the receptor for type 1 gonadotropin-releasing hormone. This receptor is a member of the seven-transmembrane, G-protein coupled receptor (GPCR) family. It is expressed on the surface of pituitary gonadotrope cells as well as lymphocytes, breast, ovary, and prostate. Following binding of gonadotropin-releasing hormone, the receptor associates with G-proteins that activate a phosphatidylinositol-calcium second messenger system. Activation of the receptor ultimately causes the release of gonadotropic luteinizing hormone (LH) and follicle stimulating hormone (FSH). Defects in this gene are a cause of hypogonadotropic hypogonadism (HH). Alternative splicing results in multiple transcript variants encoding different isoforms. More than 18 transcription initiation sites in the 5' region and multiple polyA signals in the 3' region have been identified for this gene. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SOX10
Transcription factor SOX-10 is a protein that in humans is encoded by the ''SOX10'' gene. Function This gene encodes a member of the SOX gene family, SOX (Testis-determining factor, SRY-related HMG-box) family of transcription factors involved in the regulation of embryonic development and determination of cell fate determination, cell fate. The encoded protein acts as a transcriptional activator after forming a protein complex with other proteins. This protein acts as a nucleocytoplasmic shuttle protein and is important for neural crest and peripheral nervous system development. In melanocyte, melanocytic cells, there is evidence that SOX10 gene expression may be regulated by Microphthalmia-associated transcription factor, MITF. Mutations Mutations in this gene are associated with Waardenburg–Shah syndrome and uveal melanoma. Immunostain SOX10 is used as an immunohistochemistry marker, being positive in: Topic Completed: 1 February 2014. Revised: 20 September 2019 *Neuro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FGF8
Fibroblast growth factor 8 (FGF-8) is a protein that in humans is encoded by the ''FGF8'' gene. Function The protein encoded by this gene belongs to the fibroblast growth factor (FGF) family. FGF proteins are multifunctional signaling molecules with broad mitogenic and cell survival activity, playing critical roles in embryonic development, cell proliferation, morphogenesis, tissue repair, and tumor progression. FGF8 signals primarily through fibroblast growth factor receptor 1 (FGFR1) to trigger downstream pathways involved in neural and limb development. Neural development and brain patterning FGF8 is essential for establishing the midbrain–hindbrain boundary (mesencephalon/metencephalon), a key signaling center during brain development. This region is defined by cross-repression between Otx2 and Gbx2, which helps maintain FGF8 expression. FGF8 then induces the expression of transcription factors, forming feedback loops that guide the development of the midbrain an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
