Luteinizing hormone is a hormone produced by gonadotropic cells in the anterior pituitary gland. The production of LH is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. In females, an acute rise of LH known as an LH surge, triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell–stimulating hormone (ICSH), it stimulates Leydig cell production of testosterone. It acts synergistically with follicle-stimulating hormone (FSH).
Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells. Their name comes from the Greek phagein, "to eat" or "devour", and "-cyte", the suffix in biology denoting "cell", from the Greek kutos, "hollow vessel". They are essential for fighting infections and for subsequent immunity. Phagocytes are important throughout the animal kingdom and are highly developed within vertebrates. One litre of human blood contains about six billion phagocytes. They were discovered in 1882 by Ilya Ilyich Mechnikov while he was studying starfish larvae. Mechnikov was awarded the 1908 Nobel Prize in Physiology or Medicine for his discovery. Phagocytes occur in many species; some amoebae behave like macrophage phagocytes, which suggests that phagocytes appeared early in the evolution of life.
A hormone receptor is a receptor molecule that binds to a specific chemical messenger. Hormone receptors are a wide family of proteins made up of receptors for thyroid and steroid hormones, retinoids and Vitamin D, and a variety of other receptors for various ligands, such as fatty acids and prostaglandins. Hormone receptors are of mainly two classes. Receptors for peptide hormones tend to be cell surface receptors built into the plasma membrane of cells and are thus referred to as trans membrane receptors. An example of this is Actrapid. Receptors for steroid hormones are usually found within the protoplasm and are referred to as intracellular or nuclear receptors, such as testosterone. Upon hormone binding, the receptor can initiate multiple signaling pathways, which ultimately leads to changes in the behavior of the target cells.
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. The peptide belongs to gonadotropin-releasing hormone family. It constitutes the initial step in the hypothalamic–pituitary–gonadal axis.
Gonadotropins are glycoprotein hormones secreted by gonadotropic cells of the anterior pituitary of vertebrates. This family includes the mammalian hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH), the placental/chorionic gonadotropins, human chorionic gonadotropin (hCG) and equine chorionic gonadotropin (eCG), as well as at least two forms of fish gonadotropins. These hormones are central to the complex endocrine system that regulates normal growth, sexual development, and reproductive function. LH and FSH are secreted by the anterior pituitary gland, while hCG and eCG are secreted by the placenta in pregnant humans and mares, respectively. The gonadotropins act on the gonads, controlling gamete and sex hormone production.
Self-incompatibility (SI) is a general name for several genetic mechanisms that prevent self-fertilization in sexually reproducing organisms, and thus encourage outcrossing and allogamy. It is contrasted with separation of sexes among individuals (dioecy), and their various modes of spatial (herkogamy) and temporally (dichogamy) separation.
Oligodendrocyte progenitor cells (OPCs), also known as oligodendrocyte precursor cells, NG2-glia, O2A cells, or polydendrocytes, are a subtype of glia in the central nervous system named for their essential role as precursors to oligodendrocytes. They are typically identified by coexpression of PDGFRA and NG2.
The gonadotropin-releasing hormone receptor (GnRHR), also known as the luteinizing hormone releasing hormone receptor (LHRHR), is a member of the seven-transmembrane, G-protein coupled receptor (GPCR) family. It is the receptor of gonadotropin-releasing hormone (GnRH). The GnRHR is expressed on the surface of pituitary gonadotrope cells as well as lymphocytes, breast, ovary, and prostate.
Neurotensin is a 13 amino acid neuropeptide that is implicated in the regulation of luteinizing hormone and prolactin release and has significant interaction with the dopaminergic system. Neurotensin was first isolated from extracts of bovine hypothalamus based on its ability to cause a visible vasodilation in the exposed cutaneous regions of anesthetized rats.
Kisspeptins 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, and pancreas.
The theca folliculi comprise a layer of the ovarian follicles. They appear as the follicles become secondary follicles.
Gonadotropin-releasing hormone receptor is a protein that in humans is encoded by the GNRHR gene.
The KiSS1-derived peptide 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.
Epileptogenesis is the gradual process by which a typical brain develops epilepsy. Epilepsy is a chronic condition in which seizures occur. These changes to the brain occasionally cause neurons to fire in an abnormal, hypersynchronous manner, known as a seizure.
A HEAT repeat is a protein tandem repeat structural motif composed of two alpha helices linked by a short loop. HEAT repeats can form alpha solenoids, a type of solenoid protein domain found in a number of cytoplasmic proteins. The name "HEAT" is an acronym for four proteins in which this repeat structure is found: Huntingtin, elongation factor 3 (EF3), protein phosphatase 2A (PP2A), and the yeast kinase TOR1. HEAT repeats form extended superhelical structures which are often involved in intracellular transport; they are structurally related to armadillo repeats. The nuclear transport protein importin beta contains 19 HEAT repeats.
Infertility in polycystic ovary disease (PCOS) is a hormonal imbalance in women that is thought to be one of the leading causes of female infertility. Polycystic ovary syndrome causes more than 75% of cases of anovulatory infertility.
Mladen Vranic, MD, DSc, O.C., O.Ont, FRSC, FRCP(C), FCAHS, Canadian Medical Hall of Fame[CMHF] April 3, 1930 — June 18, 2019, was a Croatian-born diabetes researcher, best known for his work in tracer methodology, exercise and stress in diabetes, the metabolic effects of hormonal interactions, glucagon physiology, extrapancreatic glucagon, the role of the direct and indirect metabolic effects of insulin and the prevention of hypoglycemia. Vranic was recognized by a number of national and international awards for his research contributions, mentoring and administration including the Orders of Canada (Officer) and Ontario.
Marta Filizola is a computational biophysicist who studies membrane proteins. Filizola's research concerns drug discovery the application of methods of computational chemistry and theoretical chemistry to biochemical and biomedical problems.
Glutamate-rich protein 4 is encoded by the gene ERICH4 and can be otherwise known as chromosome 19 open reading frame 69 (C19orf69). ERICH4 is highly conserved in mammals and exhibits overexpression in tissues of the kidneys, terminal ileum, and duodenum. The function of ERICH4 has yet to be well understood by the scientific community but is suggested to contribute to immune inflammatory responses.
Dan Theodorescu is an American physician and academic. He is the Director of the Samuel Oschin Comprehensive Cancer Institute at the Cedars-Sinai Medical Center and leader of Cedars-Sinai CANCER. From 2010 until 2018, Theodorescu was Director of the University of Colorado Cancer Center and a professor of Surgery-Urology. He has been appointed Paul Mellon Chair at the University of Virginia and Paul Bunn Chair and Distinguished University Professor at the University of Colorado.
