Endocrine - Pineal Development

From Embryology
Embryology - 15 Nov 2018    Facebook link Pinterest link Twitter link  Expand to Translate  
Google Translate - select your language from the list shown below (this will open a new external page)

العربية | català | 中文 | 中國傳統的 | français | Deutsche | עִברִית | हिंदी | bahasa Indonesia | italiano | 日本語 | 한국어 | မြန်မာ | Pilipino | Polskie | português | ਪੰਜਾਬੀ ਦੇ | Română | русский | Español | Swahili | Svensk | ไทย | Türkçe | اردو | ייִדיש | Tiếng Việt    These external translations are automated and may not be accurate. (More? About Translations)

Introduction

Developing pineal gland
Adult pineal body
Pineal gland position

The pineal gland (epiphysis cerebri) has an important role in the sleep/wake daily cycle (circadian), high melatonin plasma levels at nighttime and very low levels at daytime, and reproductive development. The gland is thought to evolutionarily to have been positioned as to be exposed to light, and hence remains a regulator of cyclic rhythms associated with day/night and day length. The pineal hormone (melatonin) has targets both in the nervous system and in many different peripheral tissues.


The embryo and fetus pineal does not produce significant amounts of melatonin, though has abundant tissue receptors. The maternal pineal gland produces melatonin in the normal circadian fashion and this melatonin can cross both the placenta and blood-brain barrier. In other species, maternal melatonin crosses the placenta into fetal circulation and may provide photoperiodic information during fetal development that influences later postnatal circadian (daily day/night) and seasonal (day length) rhythms. The pineals of non-mammalian vertebrates are photoreceptive, whereas those of mammals do not normally respond to directly light. Pineal blood supply is derived from the posterior cerebral artery choroidal branches and through the pineal recess is bathed in cerebrospinal fluid (CSF).


Postnatally in humans, the melatonin levels in premature infants is lower and delayed, but not different when calculated from conception date. Other factors such as preeclampsia, growth restriction, and nursery lighting can cause altered rhythm development. The same study has also shown that full-term infants born at home and full-term twins born in the hospital had significantly lower metabolite excretion levels than hospital-born singleton infants at the same ages despite similar body weights.[1]


Overview

  • part of epithalmus - neurons, glia and pinealocytes
  • pinealocytes secrete melatonin - cyclic nature of activity, melatonin lowest during daylight
    • inhibit hypothalamic secretion of GnRH until puberty, pineal gland then rapidly regresses.
  • other activities - possibly gamete maturation, antioxidant effect, protect neurons?


Note that there are many clinical studies investigating the possible role of melatonin in diverse health areas, from oxygen starvation at birth through to neural effects in old age.


Links: pineal | Category:Pineal | Lecture - Endocrine Development | Lecture - Head Development

Historic Pineal Papers  
1917 Pineal Region | 1932 Pineal Gland and Cysts | 1937 Human Pineal |


Endocrine Links: Introduction | BGD Lecture | Science Lecture | Lecture Movie | pineal | hypothalamus‎ | pituitary | thyroid | parathyroid | thymus | pancreas | adrenal | endocrine gonad‎ | endocrine placenta | other tissues | Stage 22 | endocrine abnormalities | Hormones | Category:Endocrine
Historic Embryology - Endocrine  
1903 Islets of Langerhans | 1904 interstitial Cells | 1908 Pancreas Different Species | 1908 Pituitary | 1908 Pituitary histology | 1911 Rathke's pouch | 1912 Suprarenal Bodies | 1914 Suprarenal Organs | 1915 Pharynx | 1916 Thyroid | 1918 Rabbit Hypophysis | 1920 Adrenal | 1935 Mammalian Hypophysis | 1926 Human Hypophysis | 1927 Hypophyseal fossa | 1932 Pineal Gland and Cysts | 1935 Hypophysis | 1937 Pineal | 1938 Parathyroid | 1940 Adrenal | 1941 Thyroid | 1950 Thyroid Parathyroid Thymus | 1957 Adrenal

Some Recent Findings

Mouse pineal E15 to E21 neuroepithelium
Mouse pineal E15 to E21 neuroepithelium[2]
  • Morphology and quantification of sheep pineal glands at pre-pubertal, pubertal and post-pubertal periods[3] "The pineal gland is a neuroendocrine organ associated with photoperiodic regulation in mammals. The aim of this study was to evaluate the pineal gland at the pre-pubertal, pubertal and post-pubertal periods by means of morphology and stereology. The study examined at total of 24 ovine pineal glands collected from healthy female Akkaraman breed. Thick sections (40 μm) were cut and treated with synaptophysin. ...The melatonin staining density was the highest in the pubertal group. The density of lipofuscin staining was higher in the pubertal and post-pubertal groups." sheep
  • Infradian Rhythm of the Content of Secretory Granules in Pinealocyte Cytoplasm in Mice and Rats[4] "The numerical density of secretory granules dense-core vesicles (DCV) in the cytoplasm of pinealocytes of the pineal gland was estimated by transmission electron microscopy in male white mice and Wistar rats. The 3-day biorhythm and lunaphase changes in the DCV content in the perikaryon and the processes of pinealocytes, which are manifested significantly in different seasons of the year, are established. The three-day biorhythm in adult male mice in comparison with younger male rats is not expressed uniformly in different phases of the moon. The in-phase manifestation of infradian biorhythms in different species of animals during the year with an unchanged daily photophase indicates the existence of common external synchronizers for mammals of these biorhythms that are not associated with the light/dark cycle." mouse | rat
  • Cellular Basis of Pineal Gland Development: Emerging Role of Microglia as Phenotype Regulator[2] "The adult pineal gland is composed of pinealocytes, astrocytes, microglia, and other interstitial cells that have been described in detail. However, factors that contribute to pineal development have not been fully elucidated, nor have pineal cell lineages been well characterized. ...The pineal gland begins as an evagination of neuroepithelium in the roof of the third ventricle. The pineal primordium initially consists of radially aligned Pax6+ precursor cells that express vimentin and divide at the ventricular lumen. After the tubular neuroepithelium fuses, the distribution of Pax6+ cells transitions to include rosette-like structures and later, dispersed cells. In the developing gland all dividing cells express Pax6, indicating that Pax6+ precursor cells generate pinealocytes and some interstitial cells. The density of Pax6+ cells decreases across pineal development as a result of cellular differentiation and microglial phagocytosis, but Pax6+ cells remain in the adult gland as a distinct population. Microglial colonization begins after pineal recess formation. Microglial phagocytosis of Pax6+ cells is not common at early stages but increases as microglia colonize the gland. In the postnatal gland microglia affiliate with Tuj1+ nerve fibers, IB4+ blood vessels, and Pax6+ cells. We demonstrate that microglia engulf Pax6+ cells, nerve fibers, and blood vessel-related elements, but not pinealocytes. We conclude that microglia play a role in pineal gland formation and homeostasis by regulating the precursor cell population, remodeling blood vessels and pruning sympathetic nerve fibers."
More recent papers  
Mark Hill.jpg
PubMed logo.gif

This table shows an automated computer PubMed search using the listed sub-heading term.

  • Therefore the list of references do not reflect any editorial selection of material based on content or relevance.
  • References appear in this list based upon the date of the actual page viewing.

References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability.

Links: References | Discussion Page | Pubmed Most Recent | Journal Searches


Search term: Pineal Embryology

Hongxuan Li, Jingyuan Li, Xiuxin Jiang, Shangming Liu, Yan Liu, Weiqian Chen, Jianmin Yang, Cheng Zhang, Wencheng Zhang Melatonin enhances atherosclerotic plaque stability by inducing prolyl-4-hydroxylase α1 expression. J. Hypertens.: 2018; PubMed 30335670

Chengliang Luo, Qiang Yang, Yuancai Liu, Shuanhu Zhou, Jiying Jiang, Russel J Reiter, Pallab Bhattacharya, Yongchun Cui, Hongwei Yang, He Ma, Jiemin Yao, Sean E Lawler, Xinmu Zhang, Jianfang Fu, Renato Rozental, Hany Aly, Mark D Johnson, E Antonio Chiocca, Xin Wang The multiple protective roles and molecular mechanisms of melatonin and its precursor N-acetylserotonin, in targeting brain injury and liver damage and in maintaining bone health. Free Radic. Biol. Med.: 2018; PubMed 30315933

Bogdan Lewczuk, Magdalena Prusik, Natalia Ziółkowska, Michał Dąbrowski, Kamila Martniuk, Maria Hanuszewska, Łukasz Zielonka Effects of Streptozotocin-Induced Diabetes on the Pineal Gland in the Domestic Pig. Int J Mol Sci: 2018, 19(10); PubMed 30304775

Mi Ping, Zhang Qiu-Ping, Li Shi-Bao, Liu Xing-Yu, Zhang Shu-Hui, Li Meng, Chen Dong-Yan, Zhao Xin, Feng Dao-Fu, Xi-Zeng Feng Melatonin protects embryonic development and maintains sleep/wake behaviors from the deleterious effects of fluorene-9-bisphenol in zebrafish (Danio rerio). J. Pineal Res.: 2018;e12530 PubMed 30269372

N Ziółkowska, B Lewczuk, M Prusik Diurnal and circadian variations in indole contents in the goose pineal gland. Chronobiol. Int.: 2018;1-16 PubMed 30252556

Older papers  
  • The Lhx9 homeobox gene controls pineal gland development and prevents postnatal hydrocephalus[5] "Lhx9 is a member of the LIM homeobox gene family. It is expressed during mammalian embryogenesis in the brain including the pineal gland. Deletion of Lhx9 results in sterility due to failure of gonadal development. The current study was initiated to investigate Lhx9 biology in the pineal gland. Lhx9 is highly expressed in the developing pineal gland of the rat with transcript abundance peaking early in development; transcript levels decrease postnatally to nearly undetectable levels in the adult, a temporal pattern that is generally similar to that reported for Lhx9 expression in other brain regions. Studies with C57BL/6J Lhx9 (-/-) mutant mice revealed marked alterations in brain and pineal development. Specifically, the superficial pineal gland is hypoplastic, being reduced to a small cluster of pinealocytes surrounded by meningeal and vascular tissue. The deep pineal gland and the pineal stalk are also reduced in size. Although the brains of neonatal Lhx9 (-/-) mutant mice appear normal, severe hydrocephalus develops in about 70 % of the Lhx9 (-/-) mice at 5-8 weeks of age; these observations are the first to document that deletion of Lhx9 results in hydrocephalus and as such indicate that Lhx9 contributes to the maintenance of normal brain structure. Whereas hydrocephalus is absent in neonatal Lhx9 (-/-)mutant mice, the neonatal pineal gland in these animals is hypo plastic."
  • Melatonin and stable circadian rhythms optimize maternal, placental and fetal physiology[6] "A number of conclusions naturally evolve from the data summarized in this review: (i) melatonin, of both pineal and placental origin, has essential functions in fetal maturation and placenta/uterine homeostasis; (ii) circadian clock genes, which are components of all cells including those in the peripheral reproductive organs, have important roles in reproductive and organismal (fetal and maternal) physiology; (iii) due to the potent antioxidant actions of melatonin, coupled with its virtual absence of toxicity, this indoleamine may have utility in the treatment of pre-eclampsia, intrauterine growth restriction, placental and fetal ischemia/reperfusion, etc. (iv) the propensity for parturition to occur at night may relate to the synergism between the nocturnal increase in melatonin and oxytocin."
  • Melatonin as a central molecule connecting neural development and calcium signaling[7] "Melatonin (MEL) is a neuroendocrine hormone secreted by the pineal gland in association with the suprachiasmatic nucleus and peripheral tissues. MEL has been observed to play a critical role in the reproductive process and in the fetomaternal interface. Extrapineal synthesis has been reported in mammalian models during pregnancy, especially by the placenta tissue."

Development Overview

  • Neuroectoderm - prosenecephalon then diencephalon
  • caudal roof, median diverticulum, epiphysis
  • Initially a hollow diverticulum, cell proliferation to solid, pinealocytes (neuroglia), cone-shaped gland innervated by epithalamus

Epithalamus consists of the pineal gland and habenular nuclei

Fetal Pineal Anatomy[8]

Superior (dorsal) view of the diencephalic-mesencephalic area of a 3.5-month-old human fetus.

The third ventricle (3 ventr) without pial covering is seen to the right in the micrograph.

The small pineal gland is a small protuberance (arrow) and merging via the broad stalk with the habenula (Ha). Sup col.: superior colliculus.

Bar = 2 mm.

Fetal pineal gland 01.jpg

Melatonin

Melatonin molecular structure
  • Melatonin is synthesized from the amino acid tryptophan within the pinealocytes.
    • Serotonin is first acetylated by aryl alkylamine N-acetyltransferase (AA-NAT), then converted to melatonin by acetyl serotonin methyl transferase (ASMT also known as hydroxyindole O-methyltransferase or HIOMT).
  • Melatonin release is stimulated by darkness and inhibited by light and is said to have neurological "chronobiotic" properties for resynchronization of sleep and circadian rhythms disturbances. In the periphery, melatonin is also involved in the regulation of several complex cycles: seasonal reproduction, body weight and energy balance.
  • Melatonin levels can be monitored by urinary excretion of the melatonin metabolite 6-sulfatoxymelatonin (aMT.6S).

Key Facts

  • less than 30 min to 60 min - serum half-life of melatonin
  • 70% - serum melatonin bound to albumin
  • 30% - diffuses in surrounding tissues
  • liver - primary metabolism
  • kidney - secondary metabolism

Melatonin Receptors

The hormone melatonin acts through receptors (high affinity G protein-coupled) embedded in the cell membrane. Three different receptor subtypes have been identified in mammals: MT1 (Mel 1a) and MT2 (Mel 1b) and a putative binding site called MT3.

  • MT1 - expressed in humans in the pars tuberalis of the pituitary gland and the suprachiasmatic nuclei of the hypothalamus.
  • MT2 - expressed in the retina.
  • MT3 - expressed in many non-mammalian vertebrates in a range of brain areas.
Links: Image - melatonergic receptors coupled via Gαi

Innervation

The gland is connected to the hypothalamus suprachiasmatic nucleus (SCN) central rhythm generator through a multi-synaptic pathway.

Nerve fibers innervating the mammalian pineal gland originate from perikarya located in the sympathetic superior cervical ganglion, the parasympathetic sphenopalatine and otic ganglia, as well as by nerve fibers originating in the central nervous system.[9]

  • sympathetic nerves - contain norepinephrine and neuropeptide Y as neurotransmitters
  • parasympathetic nerves - contain vasoactive intestinal peptide and peptide histidine isoleucine
  • trigeminal ganglion - containing substance P, calcitonin gene-related peptide, and pituitary adenylate cyclase-activating peptide


Molecular Development

Mouse pineal E15 to E21 neuroepithelium 01.jpg

Pineal gland mouse (E15 to E21)

The pineal gland develops from neuroepithelial cells that express the transcription factor Pax6 and the intermediate filament vimentin.

Panels display confocal microscopy of immunolabeled sagittal sections of rat pineal gland (PG) from embryonic day (E) 15 to E21.

  • A1-G1 show expression of Pax6 (green) and vimentin (VIM, red) in pineal precursor cells at low magnification.
  • A2-G2 display the same structures at higher magnification.
  • A3-G3 and A4-G4 show Pax6 and vimentin expression for each stage of development, respectively.

Pineal organogenesis begins around E15 as an evagination of the neuroepithelium in the dorsal diencephalon that is densely populated by Pax6-expressing cells (green). The developing PG becomes a tubular extension at E16. The orientation of Pax6/VIM+ cells is radial at these stages. At E17 the pineal neuroepithelium begins to fold and fuses at the midline. After fusion of the neuroepithelium, double immunolabeled rosette-like structures are visible in the E18-E21 developing PG. At E21 the PG has developed into a recognizable globular structure. (A1-G1) 20x; scale bar: 75 μm. (A2-G4) 60x; scale bar: 25 μm. PC, posterior commissure. SCO, subcommissural organ. 3v, third ventricle.

  • Nodal - zebrafish required for dorsal convergence of pineal precursors.[10]
  • Pax6 - rat pineal gland from E16, peak expression around E18.[11]
  • Fgf8a - zebrafish epithalamus acts permissively to promote parapineal fate.[12]
  • DARPP-32 (Dopamine- and cAMP-regulated phosphoprotein of 32 kDa) is involved in the retinal pathway transmitting photic information that resets the circadian clock.
  • OTX2, RAX, CRX, PAX4, TBX2B - also identified in development.

Links: molecular

Abnormalities

  • Pineal Hypoplasia associated with retinal disease.
  • Pineal Tumours in children are associated with abnormal puberty development.

Histology

Adult Pineal (sheep)

Adult Histology

  • Astrocytes - small dark nuclei
  • Pinealocytes - most nuclei present, larger lighter and round nuclei surrounded by a broad rim of light cytoplasm
  • Endothelial cells - nuclei in association with the vessels and capillaries traversing the tissue.
  • Cytoplasmic processes - "stringy" appearance from both pinealocytes and astrocytes


Links: large histology image


References

  1. Kennaway DJ, Goble FC & Stamp GE. (1996). Factors influencing the development of melatonin rhythmicity in humans. J. Clin. Endocrinol. Metab. , 81, 1525-32. PMID: 8636362 DOI.
  2. 2.0 2.1 Ibañez Rodriguez MP, Noctor SC & Muñoz EM. (2016). Cellular Basis of Pineal Gland Development: Emerging Role of Microglia as Phenotype Regulator. PLoS ONE , 11, e0167063. PMID: 27861587 DOI.
  3. Bolat D, Kürüm A & Canpolat S. (2018). Morphology and quantification of sheep pineal glands at pre-pubertal, pubertal and post-pubertal periods. Anat Histol Embryol , 47, 338-345. PMID: 29774950 DOI.
  4. Gerasimov AV, Kostyuchenko VP, Potapov AV, Varakuta EY, Karpova MR, Sukhanova GA & Logvinov SV. (2018). Infradian Rhythm of the Content of Secretory Granules in Pinealocyte Cytoplasm in Mice and Rats. Bull. Exp. Biol. Med. , 165, 276-279. PMID: 29931631 DOI.
  5. Yamazaki F, Møller M, Fu C, Clokie SJ, Zykovich A, Coon SL, Klein DC & Rath MF. (2015). The Lhx9 homeobox gene controls pineal gland development and prevents postnatal hydrocephalus. Brain Struct Funct , 220, 1497-509. PMID: 24647753 DOI.
  6. Reiter RJ, Tan DX, Korkmaz A & Rosales-Corral SA. (2014). Melatonin and stable circadian rhythms optimize maternal, placental and fetal physiology. Hum. Reprod. Update , 20, 293-307. PMID: 24132226 DOI.
  7. de Faria Poloni J, Feltes BC & Bonatto D. (2011). Melatonin as a central molecule connecting neural development and calcium signaling. Funct. Integr. Genomics , 11, 383-8. PMID: 21465271 DOI.
  8. Møller M, Phansuwan-Pujito P & Badiu C. (2014). Neuropeptide Y in the adult and fetal human pineal gland. Biomed Res Int , 2014, 868567. PMID: 24757681 DOI.
  9. Møller M & Baeres FM. (2002). The anatomy and innervation of the mammalian pineal gland. Cell Tissue Res. , 309, 139-50. PMID: 12111544 DOI.
  10. Aquilina-Beck A, Ilagan K, Liu Q & Liang JO. (2007). Nodal signaling is required for closure of the anterior neural tube in zebrafish. BMC Dev. Biol. , 7, 126. PMID: 17996054 DOI.
  11. Rath MF, Rohde K, Klein DC & Møller M. (2013). Homeobox genes in the rodent pineal gland: roles in development and phenotype maintenance. Neurochem. Res. , 38, 1100-12. PMID: 23076630 DOI.
  12. Clanton JA, Hope KD & Gamse JT. (2013). Fgf signaling governs cell fate in the zebrafish pineal complex. Development , 140, 323-32. PMID: 23250206 DOI.


Online Textbooks

Journals

Reviews

Ilahi S & Ilahi TB. (2018). Physiology, Pineal Gland. , , . PMID: 30247830

Chen YC, Sheen JM, Tiao MM, Tain YL & Huang LT. (2013). Roles of melatonin in fetal programming in compromised pregnancies. Int J Mol Sci , 14, 5380-401. PMID: 23466884 DOI.

Weinert D. (2005). Ontogenetic development of the mammalian circadian system. Chronobiol. Int. , 22, 179-205. PMID: 16021838

Macchi MM & Bruce JN. (2004). Human pineal physiology and functional significance of melatonin. Front Neuroendocrinol , 25, 177-95. PMID: 15589268 DOI.

Barrenetxe J, Delagrange P & Martínez JA. (2004). Physiological and metabolic functions of melatonin. J. Physiol. Biochem. , 60, 61-72. PMID: 15352385

Ekström P & Meissl H. (2003). Evolution of photosensory pineal organs in new light: the fate of neuroendocrine photoreceptors. Philos. Trans. R. Soc. Lond., B, Biol. Sci. , 358, 1679-700. PMID: 14561326 DOI.

Thomas L, Drew JE, Abramovich DR & Williams LM. (1998). The role of melatonin in the human fetus (review). Int. J. Mol. Med. , 1, 539-43. PMID: 9852259

Articles

Sun B, Wang D, Tang Y, Fan L, Lin X, Yu T, Qi H, Li Z & Liu S. (2009). The pineal volume: a three-dimensional volumetric study in healthy young adults using 3.0 T MR data. Int. J. Dev. Neurosci. , 27, 655-60. PMID: 19665543 DOI.

Al-Hussain SM. (2006). The pinealocytes of the human pineal gland: A light and electron microscopic study. Folia Morphol. (Warsz) , 65, 181-7. PMID: 16988913

Saito S, Tachibana T, Choi YH, Denbow DM & Furuse M. (2005). ICV melatonin reduces acute stress responses in neonatal chicks. Behav. Brain Res. , 165, 197-203. PMID: 16182388 DOI.

Sumida M, Barkovich AJ & Newton TH. (1996). Development of the pineal gland: measurement with MR. AJNR Am J Neuroradiol , 17, 233-6. PMID: 8938291

Search PubMed

Search Pubmed: pineal development

External Links

External Links Notice - The dynamic nature of the internet may mean that some of these listed links may no longer function. If the link no longer works search the web with the link text or name. Links to any external commercial sites are provided for information purposes only and should never be considered an endorsement. UNSW Embryology is provided as an educational resource with no clinical information or commercial affiliation.

Additional Images

Historic

Historic Disclaimer - information about historic embryology pages 
Mark Hill.jpg
Pages where the terms "Historic Textbook" and "Historic Embryology" appear on this site, and sections within pages where this disclaimer appears, indicate that the content and scientific understanding are specific to the time of publication. This means that while some scientific descriptions are still accurate, the terminology and interpretation of the developmental mechanisms reflect the understanding at the time of original publication and those of the preceding periods, these terms and interpretations may not reflect our current scientific understanding.     (More? Embryology History | Historic Embryology Papers)

Cooper ERA. The human pineal gland and pineal cysts. (1932)

Keith A. Human Embryology and Morphology. (1902) London: Edward Arnold.


Terms

Endocrine Terms (expand to view) 
  • adenohypophysis - (anterior pituitary, pars distalis) anterior part of pituitary embryonic development from surface ectoderm adenohypophyseal placode. Placode folds inward on the roof of the pharynx forming a transient structure Rathke's pouch.
  • adrenocorticotropin - (ACTH or corticotropin) anterior pituitary, peptide hormone stimulates the adrenal cortex to produce corticosteroid hormones — primarily cortisol — as well as small amounts of female and male sex hormones.
  • androstenedione - hormone precursor of testosterone and other steroidal androgens.
  • atrial natriuretic peptide - (ANP) heart, peptide hormone regulates blood pressure. A study suggests that its activating enzyme corin, and ANP together, have a role in placentation, by promoting trophoblast invasion and spiral artery remodelling. (PMID 22437503)
  • basophil cell - pituitary named by histological staining (deep blue, purple) different types produce different hormones: corticotrophs (ACTH, CRH), gonadotrophs (FSH, LH, GnRH), and thyrotrophs (TSH, TRH). See acidophil and chromophore cells.
  • C cells - parafollicular cells of the thyroid.
  • calcitonin - (CT) C cells of thyroid, peptide hormone thyroid
  • corpus luteum - ovarian endocrine organ from ovulating follicle, stimulated by hCG and supports early pregnancy by secreting progesterone, 17β-progesterone, estradiol and androstenedione.
  • corticosteroid binding globulin - (CBG) binds and transports glucocorticoids in the plasma. Globin is synthesised in the liver. adrenal
  • dihydrotestosterone - (DHT) steroidal hormone made locally by 5-alpha reductase conversion of testosterone into a more active form in genital effects.
  • dehydroepiandrosterone - (DHEA, androstenolone) adrenal cortex, gonads and brain make this steroid intermediate that may also have adult hormonal functions.
  • dehydroepiandrosterone sulphate - (DHEAS, DHEA-S) fetal adrenal cortex makes this inactive precursor of a steroid hormone.
  • dydrogesterone - clinical oral retrosteroid structurally related to progesterone, with a greater bioavailability and selectivity for the progesterone receptor.
  • estrogen (oestrogen) family of female steroidal hormones - estrone (E1), estradiol (E2), estriol (E3), and estetrol (E4) synthesised from testosterone and androstenedione, by aromatase. Also produced in male testis, and required for genital development (PMID 29438493)
  • estrone (E1) - steroid hormone with weak estrogenic activity.
  • estradiol (E2) - (oestradiol) estrogen steroid hormone with main estrogenic female activity.
  • estriol (E3) - (oestriol) steroid hormone with weak estrogenic activity.
  • estetrol (E4) (oestetrol) steroid hormone with weak estrogenic activity produced only during pregnancy.
  • follicle stimulating hormone - (FSH) pituitary glycoprotein hormone secreted by gonadotrophs (basophilic cell subgroup) acts on gametogenesis and other systems in both males and females. Females, acts on the ovary to stimulate follicle development. Negative feedback by inhibin from the developing follicle decreases FSH secretion. Males, acts on the testis Sertoli cells to increase androgen-binding protein (ABP) that binds androgens and has a role in spermatogenesis.
  • growth hormone - (GH) pituitary, peptide hormone that stimulates tissue and skeletal growth. In the ovary, growth hormone also increases granulosa cell FSH-dependent E2 production.
  • growth hormone releasing hormone - (GHRH) hypothalamus‎, protein that activates growth hormone synthesis and release from the anterior pituitary.
  • human chorionic gonadotropin - (hCG) glycoprotein hormone with 2 subunits (alpha and beta joined non covalently). Similar in structure to luteinizing hormone (LH), hCG exists in multiple hormonal and non-endocrine agents (regular hCG, hyperglycosylated hCG and the free beta-subunit of hyperglycosylated hCG). PMID 19171054
  • human chorionic somatommotropin - (hCS, CSH, placental lactogen) Placental hormone is structurally similar to both growth hormone (GH) and prolactin (PRL} and binds strongly to PRL receptors but weakly to GH receptors. Role in stimulating maternal mammary gland development. endocrine placenta
  • interstitial cell - (Leydig cell) Male testis cell secrete the androgen testosterone, required for fetal male genital tract differentiation and masculinisation after puberty.
  • Leydig cell - (interstitial cell) Male testis cell secrete the androgen testosterone, beginning in the fetus. These cells are named after Franz von Leydig (1821 - 1908) a German scientist who histologically described these cells.
  • lutenizing hormone - (LH, gonadotropin, lutropin, Interstitial Cell Stimulating Hormone, ICSH) pituitary, glycoprotein hormone acts on the gonad and has a role in male and female reproduction. Female, increase in concentration during the menstrual cycle triggers ovulation. Male, stimulates testis interstital cell production of testosterone. Gonadotrophins have been used clinically in humans for the treatment of female infertility.
  • melaocyte stimulating hormone - (MSH) pituitary, peptide hormone pituitary
  • melatonin - (N-acetyl-5-methoxytryptamine) pineal amino acid amino (precursor tryptophan) hormone involved with the diurnal cycle, melatoinin levels are high in dark, low in daylight. Also acts as an antioxidant, free radical scavenger, and anti-inflammatory molecule.
  • prolactin - (PRL) pituitary, peptide hormone pituitary
  • parathyroid - endocrine gland through parathyroid hormone (PTH) regulates calcium and phosphate levels in conjunction with parafollicular cells of the thyroid gland (calcitonin) and Vitamin D, dietary or synthesized in the skin. Develops from pharyngeal endoderm, in this case the 3rd and 4th pharyngeal pouches.
  • parathyroid hormone - (PTH) parathyroid, peptide hormone parathyroid
  • synthetic ACTH test = (synacthen test) A diagnostic test to both measure the amount of cortisol in the body and to determine the ability to produce cortisol.
  • testosterone - testis ovary steroidal hormone. In males is the androgen which regulates genital (gonadal and tract), secondary sex characteristics and neural development. The steroid is converted to the active metabolite dihydrotestosterone (DHT) by the enzyme 5-alpha reductase for the genital effects and estradiol by the enzyme aromatase for the neural effects.
  • thyroid - endocrine gland located in the neck with a developmental role in neurological development and metabolism.
  • thyroid diverticulum - the primordium of the thyroid gland, beginning as an median endodermal thickening in the floor of pharynx between the pharyngeal pouch 1 and 2.
  • thyroid hormone - (TH) thyroid amino acid derivative with two main forms (T3, T4) regulates tissue metabolic activity.
  • thyroid stimulating hormone - (TSH) pituitary protein hormone
  • ultimobranchial body - historic term for the embryonic structure that forms the parafollicular cells (C cells) of the thyroid.
Other Terms Lists  
Terms Lists: ART | Birth | Bone | Cardiovascular | Cell Division | Endocrine | Gastrointestinal | Genetic | Head | Hearing | Heart | Immune | Integumentary | NeonatalNeural | Oocyte | Palate | Placenta | Radiation | Renal | Respiratory | Spermatozoa | Statistics | Ultrasound | Vision | Historic | Drugs | Glossary


Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link



Cite this page: Hill, M.A. (2018, November 15) Embryology Endocrine - Pineal Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Endocrine_-_Pineal_Development

What Links Here?
© Dr Mark Hill 2018, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G