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Encyclopedia > Leydig cell
Leydig cell
Histological section through testicular parenchyma of a boar. 1 Lumen of Tubulus seminiferus contortus, 2 spermatids, 3 spermatocytes, 4 spermatogonia, 5 Sertoli cell, 6 Myofibroblasts, 7 Leydig cells, 8 capillaries
Section of a genital cord of the testis of a human embryo 3.5 cm. long. (Interstitial cell labeled at upper right.)
Gray's subject #258 1243
MeSH Leydig+cells
Dorlands/Elsevier c_18/12224005

Leydig cells, also known as interstitial cells of Leydig, are found adjacent to the seminiferous tubules in the testes. Leydig cells can synthesize testosterone and are often closely related to nerves. Leydig cells have round vesicular nuclei and a granular eosinophilic cytoplasm. Image File history File links Download high-resolution version (1600x1200, 697 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Leydig cell Sertoli cell Spermatocyte Spermatogonium Myofibroblast ... // Binomial name Sus scrofa Linnaeus, 1758 The Wild Boar (Sus scrofa) is the wild ancestor of the domestic pig. ... Seminiferous tubules are located in the testicles, and are the specific location of meiosis, and the subsequent creation of gametes, namely sperm. ... The term spermatid refers to the haploid male gametid that results from division of secondary spermatocytes. ... A spermatocyte is a male gametocyte which is derived from a spermatogonium. ... A Spermatogonium (plural: spermatogonia) is an intermediary male gametogonium (a kind of germ cell) in the production of spermatozoa. ... A Sertoli cell (a kind of sustentacular cell) is a nurse cell of the testes which is part of a seminiferous tubule. ... Histological section through testicular parenchyma of a boar. ... The word capillary is used to describe any very narrow tube or channel through which a fluid can pass. ... Image File history File links Gray1114. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... Elseviers logo Elsevier, the worlds largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. ... Interstitial is a generic term for referring to the space between other structures or objects. ... Human male anatomy The testicles, known medically as testes (singular testis), are the male generative glands in animals. ... Human male anatomy The testicles, known medically as testes (singular testis), are the male generative glands in animals. ... Testosterone is a steroid hormone from the androgen group. ... Eosinophilic is a technical term used by histologists. ... Organelles. ...

Contents

Nomenclature

Leydig cells are named after Franz Leydig, who discovered them in 1850. Media:Example. ... 1850 was a common year starting on Tuesday (see link for calendar). ...


Functions

They release the class of hormones called androgens (C19 steroids). They secrete testosterone, androstenedione and dehydroepiandrosterone, when stimulated by Luteinizing Hormone (LH). LH increases cholesterol desmolase activity, leading to testosterone secretion by Leydig cells. Hormone is also the NATO reporting name for the Soviet/Russian Kamov Ka-25 military helicopter. ... Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates. ... Testosterone is a steroid hormone from the androgen group. ... Androstenedione (also known as 4-androstenedione) is a 19-carbon steroid hormone produced in the adrenal glands and the gonads as an intermediate step in the biochemical pathway that produces the androgen testosterone and the estrogens estrone and estradiol. ... Dehydroepiandrosterone (DHEA), is a natural steroid hormone produced from cholesterol by the adrenal glands, the gonads, adipose tissue and the brain. ... Luteinizing hormone (LH) is a hormone synthesized and secreted by gonadotropes in the anterior lobe of the pituitary gland. ...


FSH (Follicle Stimulating Hormone) increases the response of Leydig cells to LH (Luteinizing Hormone) by up regulation. (FSH increases the number of receptors for LH) Follicle stimulating hormone (FSH) is a hormone produced by gonadotropes in the anterior pituitary gland. ... Follicle stimulating hormone (FSH) is a hormone produced by gonadotropes in the anterior pituitary gland. ...


Leydig cells form during the 16th and 20th week of gestation. They are quiescent until puberty. Gestation is the carrying of an embryo or fetus inside a female viviparous animal. ... In cell biology, quiescence is the state of cell when it is not dividing. ... Puberty refers to the process of physical changes by which a childs body becomes an adult body capable of reproduction. ...


See also

Sertoli-Leydig cell tumours are part of the sex cord-stromal tumour group of ovarian neoplasms. ... A Sertoli cell (a kind of sustentacular cell) is a nurse cell of the testes which is part of a seminiferous tubule. ...

External links

v  d  e
Male reproductive system
Scrotum : layers (skin, Dartos, External spermatic fascia, Cremaster, Internal spermatic fascia) | Perineal raphe | Spermatic cord

Testes: layers (Tunica vaginalis, Tunica albuginea), Appendix, Mediastinum, Lobules, Septa, Leydig cell, Sertoli cell, Blood-testis barrier Who Named It is a Norwegian database of several thousand eponymous medical signs and the doctors associated with their identification. ... For the unrelated Jesuit university in Chestnut Hill, see Boston College. ... The human male reproductive system is a series of organs located outside of the body and around the pelvic region of a male. ... In some male mammals, the scrotum is a bag of skin and muscle containing the testicles. ... The dartos is a layer of smooth muscular fiber. ... The external spermatic fascia (intercrural or intercolumnar fascia) is a thin membrane, prolonged downward around the surface of the cord and testis. ... The cremaster muscle is a muscle that covers the testis. ... The internal spermatic fascia (infundibuliform fascia) is a thin layer, which loosely invests the cord; it is a continuation downward of the transversalis fascia. ... The perineal raphe extends from the anus, through the mid-line of the scrotum (scrotal raphe) and upwards through the posterior mid-line aspect of the penis (penile raphe). ... Male Anatomy The spermatic cord is the name given to the cord-like structure formed by the vas deferens and surrounding tissue (veins, arteries, nerves, and lymphatic vessels) that run from the abdomen down to each testicle. ... balls in your mouth The testicles, or testes (singular testis), are the male generative glands in animals. ... This page meets Wikipedias criteria for speedy deletion. ... For other structures with the same name, see Tunica albuginea. ... The Appendix testis is a vestigial remnant of the Müllerian duct present on on the upper testis attached to the tunica vaginalis about 90% of the time. ... The mediastinum testis extends from the upper to near the lower extremity of the gland, and is wider above than below. ... The glandular structure of the testis consists of numerous lobules. ... Each lobule of the testis is contained in one of the intervals between the fibrous septa which extend between the mediastinum testis and the tunica albuginea, and consists of from one to three, or more, minute convoluted tubes, the tubuli seminiferi. ... A Sertoli cell (a kind of sustentacular cell) is a nurse cell of the testes which is part of a seminiferous tubule. ... The blood-testis barrier (abbreviated as BTB) is a barrier between the blood vessels and the seminiferous tubules of the animal testes. ...


Spermatogenesis: Spermatogonium, Spermatocytogenesis, Spermatocyte, Spermatidogenesis, Spermatid, Spermiogenesis, Spermatozoon This article or section is in need of attention from an expert on the subject. ... A Spermatogonium (plural: spermatogonia) is an intermediary male gametogonium (a kind of germ cell) in the production of spermatozoa. ... Spermatocytogenesis is the male form of gametocytogenesis. ... Spermatogenesis refers to the creation, or genesis, of sperm cells, which occurs in the male gonads or testes. ... it is the creation of spermatids from secondary spermatocytes through mitosis ... The term spermatid refers to the haploid male germ cell that results from secondary spermatocyte division. ... Spermiogenesis is the creation of a spermatozoon from a spermatid. ... A spermatozoon or spermatozoan ( spermatozoa), from the ancient Greek σπέρμα (seed) and ζῷον (living being) and more commonly known as a sperm cell, is the haploid cell that is the male gamete. ...


seminal tract: Seminiferous tubules (Tubuli seminiferi recti, Rete testis, Efferent ducts) | Epididymis  (Appendix) | Vas deferens | Ejaculatory duct  Seminal colliculus Human male anatomy The testicles, known medically as testes (singular testis), are the male generative glands in animals. ... The tubuli seminiferi recti (or tubuli recti, or straight seminiferous tubules) enter the fibrous tissue of the mediastinum, and pass upward and backward, forming, in their ascent, a close net-work of anastomosing tubes which are merely channels in the fibrous stroma, lined by flattened epithelium, and having no proper... Rete testis is an anastomosing network of delicate tubules located in the testicular hilum that carries sperm from the seminiferous tubules to the vasa efferentia. ... The efferent ducts are part of the testes and connect the rete testis with the epididymis. ... Male Anatomy The epididymis is part of the human male reproductive system and is present in all male mammals. ... On the head of the epididymis is a second small stalked appendage (sometimes duplicated); it is named the appendix of the epididymis (pedunculated hydatid), and is usually regarded as a detached efferent duct. ... The vas deferens, also called ductus deferens, (Latin: carrying-away vessel) is part of the male anatomy of some species, including humans. ... The Ejaculatory ducts are part of the human male anatomy, which cause the reflex action of ejaculation. ... At the forepart of the urethral crest, below its summit, is a median elevation, the seminal colliculus, upon or within the margins of which are the following: the orifices of the prostatic utricle the slit-like openings of the ejaculatory ducts. ...


urinary tract: Internal urethral orifice | Urethra (Prostatic, Intermediate, Spongy) | Urethral crest | Urethral gland | External urethral orifice The internal urethral orifice is placed at the apex of the trigonum vesicae, in the most dependent part of the bladder, and is usually somewhat crescentic in form; the mucous membrane immediately behind it presents a slight elevation, the uvula vesicae, caused by the middle lobe of the prostate. ... In anatomy, the urethra is a tube which connects the urinary bladder to the outside of the body. ... The prostatic urethra, the widest and most dilatable part of the canal, is about 3 cm. ... The intermediate part of male urethra (membranous portion) is the shortest, least dilatable, and, with the exception of the external orifice, the narrowest part of the canal. ... The spongy urethra (cavernous portion of urethra, penile urethra) is the longest part of the urethra, and is contained in the corpus cavernosum urethraeæ. It is about 15 cm. ... Upon the posterior wall of the prostatic urethra is a narrow longitudinal ridge, the urethral crest, formed by an elevation of the mucous membrane and its subjacent tissue. ... The term urethral gland (or Littre gland) is used to refer to any of the many glands that branch off of the wall of the urethra of male mammals. ... The external urethral orifice (urinary meatus) is placed about 2. ...


Penis: Corpus cavernosum | Corpus spongiosum | Navicular fossa of male urethra | Glans penis | Fundiform ligament | Suspensory ligament | Foreskin | Frenulum  The penis (plural penises, penes) is an external male sexual organ. ... A corpus cavernosum is one of a pair of a sponge-like regions of erectile tissue which contain most of the blood in the male penis during erection. ... Corpus spongiosum (Plural: Corpora Spongiosa) (also known as corpus cavernosum urethrae in older texts) is the mass of spongy tissue surrounding the male urethra within the penis. ... The cavernous portion of the urethra is narrow, and of uniform size in the body of the penis, measuring about 6 mm. ... The glans penis is the sensitive erectile tip of the penis. ... The fundiform ligament is a specialization of the superficial (Scarpas) fascia of the abdomen. ... In males, the suspensory ligament of the penis is attached to the pubic symphysis, which holds the penis close to the pubic bone and supports it when erect. ... The Male Anatomy The foreskin or prepuce (a technically broader term that also includes the clitoral hood, the homologous structure in women) is a retractable double-layered fold of skin and mucous membrane that covers the glans penis and protects the urinary meatus when the penis is not erect. ... The word frenulum on its own is often used for the frenulum of prepuce of penis, which is an elastic band of tissue under the glans penis that connects to the prepuce, or foreskin to the vernal mucosa, and helps contract the prepuce over the glans. ...


accessory glands: Seminal vesicles  (Excretory duct of seminal gland) | Prostate  (Prostatic utricle, Prostatic sinus) | Bulbourethral glands  Male Anatomy The seminal vesicles are a pair of glands on the posterior surface of the urinary bladder of males. ... Each seminal vesicle consists of a single tube, coiled upon itself, and giving off several irregular cecal diverticula; the separate coils, as well as the diverticula, are connected together by fibrous tissue. ... Male Anatomy The prostate is an exocrine gland of the male mammalian reproductive system. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... On either side of the urethral crest is a slightly depressed fossa, the prostatic sinus, the floor of which is perforated by numerous apertures, the orifices of the prostatic ducts from the lateral lobes of the prostate. ... The bulbourethral glands (or Cowpers glands) secrete a clear fluid known as pre-ejaculate or Cowpers fluid (colloquially known as pre-cum) which is generated upon sexual arousal. ...


  Results from FactBites:
 
Non-Germ Cell Tumors of the Testis - Tumors of the Testis (577 words)
Approximately 5-6% of all testis tumors are non-germ cell tumors of the testis.
Leydig cell tumors are the most common non-germ cell tumors of the testis and account for 1-3% of all testicular tumors.
Reinke crystals are fusiform-shaped cytoplasmic inclusions that are pathognomonic for Leydig cells.
Endotext.com - Endocrinology Of Male Reproduction, Testicular Cancer Pathogenesis, Diagnosis and Endocrine Aspects (5779 words)
Leydig cells are located in the interstitial compartment of the testis and are involved in the development of secondary male characteristics and maintenance of spermatogenesis.
However, Leydig cell hyperplasia is distinct from tumors that are usually solitary, and the role of the LH receptor and G protein mutations in the tumorigenesis may be limited to few cases (105, 107).
Leydig cell tumors are always benign in children and can be treated with surgical enucleation when the tumor is encapsulated (97), whereas in adults malignant tumors have been found in 10-15 % of patients, and inguinal orchidectomy remains the treatment of choice (110).
  More results at FactBites »


 

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