DOCSLIB.ORG

Endocrine Glands by Prof. Punita Manik [PDF]

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Endocrine Glands by Prof. Punita Manik [PDF] Endocrine Glands Dr Punita Manik Professor Department of Anatomy K G’s Medical University U P Lucknow Endocrine Glands Discrete organs Association with organs • Pituitary • Islet of Langerhans (Hypophysis cerebri) • Interstitial cells of Leydig • Thyroid • Ovarian Follicle & • Parathyroid Corpus luteum • Adrenal(Suprarenal) • Chorion • Pineal • Lacis cells, JG cells • Enteroendocrine cells Thyroid Composed • Stroma – capsule and intralobular loose connective tissue • Parenchyma - thyroid follicles Parenchyma-Thyroid Follicles • Lined by cuboidal epithelium • Height of the follicular cells varies with the secretory activity of the gland • Cells secrete T3 and Lumen filled with colloid or Thyroglobulin- T4 inactive form of thyroid hormones Thyroid • In the same gland, active and resting follicles are seen • Resting • Active • Secretory activity is under the control of TSH of adenohypophysis Thyroid Resting and active Follicle Parafollicular cells • Also known as C cells of Clear cells • Large pale staining cells , granular cytoplasm • Present either singly or in groups • Within the follicle or between the follicles in the interfollicular space • Those within the follicle lie between the basement membrane and the follicular cells • Secrete Thyrocalcitonin or Calcitonin • Calcitonin lowers blood calcium level Parathyroid • STROMA- capsule and septa • PARENCHYMA- secretory cells arranged in clusters or anastomosing cords • 2 type of cells • Chief cells Or Principal cells • Oxyphil cells Parathyroid Parathyroid • Chief Cells-small, Basophilic, in large nos • Oxyphil cells- Large, eosinophilic, small no Chief cells- secrete Parathromone or Parathyroid hormone • Parathyroid hormone Increases Calcium Level Decreases phosphate Level in blood Parathyroid Pituitary Gland Ant & Post Pituitary Cells of Anterior Pituitary • Granular Cells arranged in irregular cords or clusters • Based on the affinity of granules for specific stains: Chromophils & Chromophobes • Chromophils: Darkly stained because of stained granules • Chromophobes: Poorly stained as no or few granules Cells of Anterior Pituitary Acidophils and Basophils Chromophils Acidophils Basophils • Shape: Round or oval • Large, rounded or • Stain with orange G or polyhedral Erythrosin • PAS + • Somatotrophs and • Gonadotrophs (LH, Lactotrophs FSH) Thyrotrophs(TSH), • Secrete GH and Corticpotrophs(ACTH Prolactin and MSH) Anterior & Posterior Pituitary Posterior Pituitary Numerous unmyelinated nerve fibres which are axons of neurons located in the Hypothalamus Arising from supraoptic and Paraventricular Nuclei Supporting cells between them are pituicytes Anterior & Posterior Pituitary Pituitary Gland Adrenal Adrenal Cortex: 3 zones • Zona Glomerulosa • Zona fasciculata • Zona Reticularis • Cells of cortex has characteristic features of steroid formation: • Cells have many mitochondria with long tubular cristae and smooth endoplasmic reticulum where enzymes for steroid synthesis are found • Secretory activity under the control of ACTH Adrenal Gland Adrenal Z. Glomerulosa • Rounded or arched clusters of pyramidal cells, acidophilic cytoplasm with lipid droplets • Fenestrated capillaries are found among the cluster of cells Adrenal Z. Fasciculata • Straight parallel cords cords of polyhedral cells, pale staining cytoplasm with lipid droplets • Lipid droplets give vacuolated or spongy appearance known as spongiocytes • Fenestrated capillaries seen between the cord of cells Zona Glomerulosa and Zona Fasciculata Adrenal Z Reticularis • Small, more acidophilic cells • irregular anastomosing cords of cells • Cells have elongated mitochondria,glycogen, lipofuscin pigments and few lipid droplets Adrenal Medulla • Clumps or cords of chromaffin cells • Polyhedral in shape with few fenestrated capillaries in between • Also contains parasympathetic ganglion cells Adrenal-chromaffin cells • Derived from Neural crest cells • Are modified sympathetic postganglionic neurons • Stain with chromium salts • Catecholamines are oxidized to brown compound- Chromaffin reaction. Chromaffin cells of Medulla Difference between cells of Cortex and Medulla Cortex Medulla • Under the control of ACTH • Neural Control as innervated by modified sympathetic postganglionic neurons • Cells do not accumulate their hormones in granules. They synthesize and • Cells accumulate and store secrete only on demand secretory products in their granules Adrenal Gland Pineal Gland (Epiphysis) Main cells- Pinealocytes- modified Neurons Other cells-Astroglial cells Pineal Gland (Epiphysis) Brain sand or Corpora arenacea-concentric rings of Ca & Mg Po4 Pineal gland MCQ • Parafollicular cells are present in which of the following endocrine glands? 1. Parathyroid 2. Suprarenal 3. Thyroid 4. Pancreas MCQ • Which part of the hypophysis cerebri contains Herring Bodies? 1. Pars anterior 2. Pars posterior 3. Pars tuberalis 4. Pars intermedia MCQ • Adenohypophysis contains all type of cells EXCEPT? 1.Chromophobes 2. Acidophils 3. Basophils 4. Pituicytes MCQ • The active follicles of thyroid gland are lined by 1. Simple squamous epithelium 2. Simple cuboidal epithelium 3. Simple columnar epithelium 4. Stratified cuboidal epithelium.
Load more

Recommended publications
  • Human General Histology
    135 اووم څپرکي انډوکراين سيستم (Endocrine system) (hormones) (target cells) (receptors) autonomic (sinusoids) ductless glands thyroid gland Pineal gland Hypophysis cerebri(pituitary glands) supra renal( adrenal glands) parathyroid glands 136 اووم څپرکي انډوکراين سيسټم islets cell corpora lutea interstitial tissue (placenta) GIT amines neurotransmitters amines neuromodulator 137 اووم څپرکي انډوکراين سيسټم APUD cells neuroendocrine system system adrenaline, (amino acid derivatives) thyroxin noradrenalin thyroid vasopressin encephalin (small peptides) releasing hormone(TRH) TSH(thyroid stimulating parathormone hormone) cortisol Testosterone estrogen (steroids) 5,12,3 (Hypophysis Cerebri) (brain) pituitary gland (stalk) Ventricle infundibulum stalk pituitary fossa sphenoid pineal hypothalamus body 138 اووم څپرکي انډوکراين سيسټم Hypophysis cerebri Pars pars anterior pars nervosa pars posterior intermediate hypothalamus infundibulum infundibulum stalk )Pars posterior neurohypophysis median eminence (tuber cinereum) infundibulum pars neurohypophysis median eminence pars intermediate pars distalis anterior Adenohypophysis infundibulum pars anterior pars tuberalis adenohypophysis 139 اووم څپرکي انډوکراين سيسټم Adenohypophysis pars intermediate pars anterior adenohypophyisis Pars anterior fenestrated sinusoids (cords) chromophil chromophobic acidophil chromophil basophils orange G eosin PAS-positive hematoxylline Beta cells basophil Alpha cells Acidophil basophils acidophil (dese cored vesicles) alpha Beta Histochemical 140 اووم څپرکي انډوکراين
    [Show full text]
  • Pineal Calcification, Melatonin Production, Aging, Associated
    molecules Review Pineal Calcification, Melatonin Production, Aging, Associated Health Consequences and Rejuvenation of the Pineal Gland Dun Xian Tan *, Bing Xu, Xinjia Zhou and Russel J. Reiter * Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA; [email protected] (B.X.); [email protected] (X.Z.) * Correspondence: [email protected] (D.X.T.); [email protected] (R.J.R.); Tel.: +210-567-2550 (D.X.T.); +210-567-3859 (R.J.R.) Received: 13 January 2018; Accepted: 26 January 2018; Published: 31 January 2018 Abstract: The pineal gland is a unique organ that synthesizes melatonin as the signaling molecule of natural photoperiodic environment and as a potent neuronal protective antioxidant. An intact and functional pineal gland is necessary for preserving optimal human health. Unfortunately, this gland has the highest calcification rate among all organs and tissues of the human body. Pineal calcification jeopardizes melatonin’s synthetic capacity and is associated with a variety of neuronal diseases. In the current review, we summarized the potential mechanisms of how this process may occur under pathological conditions or during aging. We hypothesized that pineal calcification is an active process and resembles in some respects of bone formation. The mesenchymal stem cells and melatonin participate in this process. Finally, we suggest that preservation of pineal health can be achieved by retarding its premature calcification or even rejuvenating the calcified gland. Keywords: pineal gland; calcification; melatonin; aging; neurodegenerative diseases; rejuvenation 1. Introduction Pineal gland is a unique organ which is localized in the geometric center of the human brain. Its size is individually variable and the average weight of pineal gland in human is around 150 mg [1], the size of a soybean.
    [Show full text]
  • Histology Histology
    HISTOLOGY HISTOLOGY ОДЕСЬКИЙ НАЦІОНАЛЬНИЙ МЕДИЧНИЙ УНІВЕРСИТЕТ THE ODESSA NATIONAL MEDICAL UNIVERSITY Áiáëiîòåêà ñòóäåíòà-ìåäèêà Medical Student’s Library Серія заснована в 1999 р. на честь 100-річчя Одеського державного медичного університету (1900–2000 рр.) The series is initiated in 1999 to mark the Centenary of the Odessa State Medical University (1900–2000) 1 L. V. Arnautova O. A. Ulyantseva HISTÎLÎGY A course of lectures A manual Odessa The Odessa National Medical University 2011 UDC 616-018: 378.16 BBC 28.8я73 Series “Medical Student’s Library” Initiated in 1999 Authors: L. V. Arnautova, O. A. Ulyantseva Reviewers: Professor V. I. Shepitko, MD, the head of the Department of Histology, Cytology and Embryology of the Ukrainian Medical Stomatologic Academy Professor O. Yu. Shapovalova, MD, the head of the Department of Histology, Cytology and Embryology of the Crimean State Medical University named after S. I. Georgiyevsky It is published according to the decision of the Central Coordinational Methodical Committee of the Odessa National Medical University Proceedings N1 from 22.09.2010 Навчальний посібник містить лекції з гістології, цитології та ембріології у відповідності до програми. Викладено матеріали теоретичного курсу по всіх темах загальної та спеціальної гістології та ембріології. Посібник призначений для підготовки студентів до практичних занять та ліцензійного екзамену “Крок-1”. Arnautova L. V. Histology. A course of lectures : a manual / L. V. Arnautova, O. A. Ulyantseva. — Оdessa : The Оdessa National Medical University, 2010. — 336 p. — (Series “Medical Student’s Library”). ISBN 978-966-443-034-7 The manual contains the lecture course on histology, cytology and embryol- ogy in correspondence with the program.
    [Show full text]
  • Other Useful Books
    Other Useful Books Dictionaries: Leeson TS, Leeson CR: Histology, 4th ed. Philadel­ phia: Saunders, 1981. Dorland's Illustrated Medical Dictionary, 26th ed. Lentz, TL: Cell Fine Structure. Philadelphia: Saun­ Philadelphia: Saunders, 1981. ders, 1971. Melloni's Illustrated Medical Dictionary. Balti­ Rhodin JAG: Histology, A Text and Atlas. New more: Williams and Wilkins, 1979. York: Oxford University Press, 1974. Stedman's Illustrated Medical Dictionary, 24th ed. Williams PL, Warwick R: Gray's Anatomy, 36th Baltimore: Williams and Wilkins, 1982. English edition. Philadelphia: Saunders, 1980. Weiss L, Greep ROO: Histology, 4th ed. New York: McGraw-Hill, 1977. Textbooks: Histology and Cytology Wheater PR, Burkitt HG, Daniels VG: Functional Arey LB: Human Histology, 4th ed. Philadelphia: Histology. Edinburgh: Churchill Livingstone, 1979. Saunders, 1974. Bloom W, Fawcett DW: A Textbook of Histology, Textbooks: Pathology 10th ed. Philadelphia: Saunders, 1974. Anderson WAD, Kissane JM: Pathology, 7th ed. Borysenko M, Borysenko J, Beringer T, Gustafson St. Louis: Mosby, 1977. A: Functional Histology. A Core Text. Boston: Lit­ tle, Brown, 1979. Anderson WAD, Scotti TM: Synopsis of Pathology, 10th ed. St. Louis: Mosby, 1980. Copenhaver WM, Kelly DE, Wood RL: Bailey's Golden A: Pathology. Understanding Human Dis­ Textbook of Histology, 17th ed. Baltimore: Wil­ ease. Baltimore: Williams and Wilkins, 1982. liams and Wilkins, 1978. King D, Geller LM, Krieger P, Silva F, Lefkowitch Cowdry EV: A Textbook of Histology, 4th ed. Phila­ JH: A Survey of Pathology. New York: Oxford delphia: Lea and Febiger, 1950. University Press, 1976. Dyson RD: Cell Biology. A Molecular Approach, Robbins SL, Cotran RS: Pathologic Basis of Dis­ 2nd ed. Boston: Allyn and Bacon, 1978.
    [Show full text]
  • Endocrine System
    Endocrine system Hormonal regulation Endocrine glands • Glands w/o ducts • Secretory cells release their products, hormones, into the extracellular space and blood stream • Alternatively, the hormones may affect neighbor cells (paracrine) • Structure: • c.t. – capsule + septs • irregular clumps or cords of the cells • network of capillaries • fenestrated capillaries • sinusoids Hypophysis – pituitary gland Pituitary gland – anterior pituitary Pituitary gland – anterior pituitary Chromophilic cells - Acidophilic cells (produce proteins) somatotrophs mammotrophs (or lactotrophs) - Basophilic cells (produce glycoproteins) thyrotrophs produce thyroid stimulating hormone (TSH or thyrotropin). gonadotrophs produce follicle stimulating hormone (FSH) and luteinizing hormone (LH) corticotrophs (or adrenocorticolipotrophs) Chromophobic cells Adenohypophysis Adenohypophysis orange G + PAS Neurohypophysis x Adenohypophysis Neurohypophysis - structure Structure unmyelinated nerve fibres derived from neurosecretory cells of the supraoptic and paraventricular hypothalamic nuclei pituicytes /neuroglia/ Function Two hormones are oxytocin, which stimulates the contraction of smooth muscle cell in the uterus and participates in the milk ejection reflex, and antidiuretic hormone (ADH or vasopressin), which facilitates the concentration of urine in the kidneys and, thereby, the retention of water. Usually only the oval or round nuclei of the pituicytes are visible. Hypothalamic nerve fibres typically terminate close to capillaries. Scattered, large
    [Show full text]
  • |||GET||| Pancreatic Islet Biology 1St Edition
    PANCREATIC ISLET BIOLOGY 1ST EDITION DOWNLOAD FREE Anandwardhan A Hardikar | 9783319453057 | | | | | The Evolution of Pancreatic Islets Advanced search. The field of regenerative medicine is rapidly evolving and offers great hope for the nearest future. Easily read eBooks on Pancreatic Islet Biology 1st edition phones, computers, or any eBook readers, including Kindle. Help Learn to edit Community portal Recent changes Upload file. Pancreatic Islet Biologypart of the Stem Cell Biology and Regenerative Medicine series, is essential reading for researchers and clinicians in stem cells or endocrinology, especially those focusing on diabetes. Because the beta cells in the pancreatic islets Pancreatic Islet Biology 1st edition selectively destroyed by an autoimmune process in type 1 diabetesclinicians and researchers are actively pursuing islet transplantation as a means of restoring physiological beta cell function, which would offer an alternative to a complete pancreas transplant or artificial pancreas. Strategies to improve islet yield from chronic pancreatitis pancreases intended for islet auto-transplantation 6. About this book This comprehensive volume discusses in vitro laboratory development of insulin-producing cells. Junghyo Jo, Deborah A. Show all. Comparative Analysis of Islet Development. Leibson A. However, type 1 diabetes is the result of the autoimmune destruction of beta cells in the pancreas. Islets can influence each other through paracrine and autocrine communication, and beta cells are coupled electrically to six to seven other beta cells but not to other cell types. Pancreatic Islet Biologypart of the Stem Cell Biology and Regenerative Medicine Pancreatic Islet Biology 1st edition, is essential reading for researchers and clinicians in stem cells or endocrinology, especially those focusing on diabetes.
    [Show full text]
  • Invited Review Comparative Histology Of
    Histol Histopathol (1998) 13: 851-870 Histology and 001: 10.14670/HH-13.851 Histopathology http://www.hh.um.es From Cell Biology to Tissue Engineering Invited Review Comparative histology of pineal calcification B. Vigh1, A. Szel1, K. Debreceni,1 Z. Fejer1, M.J. Manzano e SIIva2 and I. Vigh-Teichmann3 1Photoneuroendocrine Laboratory of the Department of Human Morphology and Developmental Biology, Semmelweis Medical University, Budapest, Hungary, 20ccupational Health Service, Hospital dos Capuchos, Lisbon, Portugal and 3Paul Gerhardt Foundation, Lutherstadt Wittenberg, Germany Summary. The pineal organ (pineal gland, epiphysis organelles and exhibit alkaline phosphatase reaction in cerebri) contains several calcified concretions called the rat and mink, an indicatfon of a presumable " brain sand" or acervuli (corpora arenacea). These osteoblast-like activity. Using Kassa's method for the concretions are conspicuous with imaging techniques staining of calcium deposits, a higher calcium and provide a useful landmark for orientation in the concentration was detected in the rat pineal than in the diagnosis of intracranial diseases. Predominantly surrounding brain tissue. Since in parathyroidectomised composed of calcium and magnesium salts, corpora rats calcified deposits are larger and more numerous than arenacea are numerous in old patients. In smaller in controls, the regulation of the production of acervuli number they can be present in children as well. The by the parathyroid gland has also been postulated. degree of calcification was associated to various In most of submammalian species, the pineal organs diseases. However, the presence of calcified concretions (pineal-, parapineal organ, frontal organ, parietal eye) seems not to reflect a specific pathological state. are photoreceptive and organized similarly to the retina.
    [Show full text]
  • Endocrine System
    Endocrine System Dr. Rajaa Ali Structure and Function of the Pituitary Gland Anterior Lobe of the Pituitary Gland (Adenohypophysis) The anterior lobe of the pituitary gland regulates other endocrine glands . Most of the anterior lobe of the pituitary gland has the typical organization of endocrine tissue. The cells are organized in clumps and cords separated by fenestrated sinusoidal capillaries of relatively large diameter. These cells respond to signals from the hypothalamus and synthesize and secrete a number of pituitary hormones . Four hormones of the anterior lobe—adrenocorticotropic hormone (ACTH), thyroidstimulating (thyrotropic) hormone (TSH, thyrotropin), follicle-stimulating hormone (FSH), and luteinizing hormone (LH)—are called tropic hormones because they regulate the activity of cells in other endocrine glands throughout the body. The two remaining hormones of the anterior lobe, growth hormone (GH) and prolactin (PRL), are not considered tropic because they act directly on target organs that are not endocrine. The cells within the pars distalis vary in size, shape, and staining properties. The cells are arranged in cords and nests with interweaving capillaries. Histologists identified three types of cells according to their staining reaction, namely, basophils (10%), acidophils (40%), and chromophobes (50%) Pars Intermedia. The pars intermedia surrounds a series of small cystic cavities that represent the residual lumen of Rathke’s pouch fig.(2). The parenchymal cells of the pars intermedia surround colloid-filled follicles. The cells lining these follicles appear to be derived either from folliculo-stellate cells or various hormone-secreting cells, pars intermedia have vesicles larger than those found in the pars distalis.. The pars intermedia contains basophils and chromophobes (Fig.
    [Show full text]
  • GLOSSARY of HISTOLOGICAL & MICRO-ANATOMICAL TERMS
    GLOSSARY of HISTOLOGICAL & MICRO-ANATOMICAL TERMS Abbreviations: ( ) plural form in brackets • A. Arabic abb. abbreviation • c. circa (= about) • F. French adj. adjective • G. Greek • Ge. German cf. compare • L. Latin dim. diminutive • NA. Nomina anatomica q.v. which see • OF. Old French A-band abb. of anisotropic band G. anisos = unequal + tropos = turning; meaning having not equal properties in every direction; transverse bands in living skeletal muscle which rotate the plane of polarised light, cf. I-band. Abbé, Ernst. 1840-1905. German physicist; mathematical analysis of optics as a basis for constructing better microscopes; devised oil immersion lens; Abbé condenser. absorption L. absorbere = to suck up. acervulus L. = sand, gritty; brain sand (cf. psammoma body). acetylcholine an ester of choline found in many tissue, synapses & neuromuscular junctions, where it is a neural transmitter. acetylcholinesterase enzyme at motor end-plate responsible for rapid destruction of acetylcholine, a neurotransmitter. acidophilic adj. L. acidus = sour + G. philein = to love; affinity for an acidic dye, such as eosin staining cytoplasmic proteins. acinus (-i) L. = a juicy berry, a grape; applied to small, rounded terminal secretory units of compound exocrine glands that have a small lumen (adj. acinar). acrosome G. akron = extremity + soma = body; head of spermatozoon. actin polymer protein filament found in the intracellular cytoskeleton, particularly in the thin (I-) bands of striated muscle. adenohypophysis G. ade = an acorn + hypophyses = an undergrowth; anterior lobe of hypophysis (cf. pituitary). adenoid G. " + -oeides = in form of; in the form of a gland, glandular; the pharyngeal tonsil. adipocyte L. adeps = fat (of an animal) + G. kytos = a container; cells responsible for storage and metabolism of lipids, found in white fat and brown fat.
    [Show full text]
  • Archiv Für Naturgeschichte
    © Biodiversity Heritage Library, http://www.biodiversitylibrary.org/; www.zobodat.at L Mammalia für 1903. Von Dr. Curt Hennings, Privatdocent. Karlsruhe. (Inhaltsverzeichnis befindet sich am Schlüsse des Berichtes.) I. Verzeichnis der Veröffentlichungen. — (Anonymus 1). Die letzten Biber in Deutschland. — Zwinger u. Feld 78. — (Anonymus 2). Der Biber an der Elbe. — 1. c. 1391. — (Anonymus 3). Schneehasenkreuzungen. — Jagdfreund 247. — (Anonymus 4). Hunde-Wölfe. — Waidwerk i. Wort u. Bild 7. — (Anonymus 5). Ranzende Iltisse? — Jagdfreund 38. — (Anonymus 6). Ein Rehkrüppel. — Zwinger u. Feld 78. — (Anonymus 7). Sechser- Gehörn einer Ricke mit Zwitterbildung. — Hubertus 239. — (Anonymus 8). A new egyptian Mammal from the Fayum. — Geol. Mag. (4) X. 529—31. 2 Tafeln. Abel, 0. (1). Die Ursache der Asymmetrie des Zahnwalschädels. — Sitzungsber. Akad. Wien. CXI. 510—526. 1 Taf. — (3). Zwei neue Menschenaffen aus den Leithakalbildungen des Wiener Beckens. — Centralbl. Mineral. 1903. 176—182. Mit Ab- bildg. (Auch in: Sitzungsber. Akad. Wien CXI. 1171—1207). — (3). Die fossilen Sirenen des Wiener Beckens. — Verh. geol. Reichsanst. 1903. 72. Acquisto, V. Particolaritä di struttura della membrana amniotica della Cavia. — Monit. Zool. Ital. Anno XIV. 173—182. 5 Figg. Adachi, B. Hautpigment beim Menschen und bei den Affen. — Zeitschr. Morphol. Anthropol. Stuttgart VI. 1—131. 3 Taf. L. Adams, E. A contribution to our knowledge of the Mole ( Talfa europaea) — Mem. Manchester Soc. XLVIII. 39 pgg. 1 Taf. Addario, C. Süll' apparente membrana limitante della retina ciliare. — Monit. Zool. Ital. XIII, Suppl. 16—18. Adloff, P. (1). Zur Kenntnis des Zahnsystems von Hyrax. — Zeit- schr. Morph. Anthropol. Stuttg. V. 181—200. 2 Taf. Aich. f. Natiivgesch. 70 Jahrg.
    [Show full text]
  • Two Components of the Pineal Organ in the Mink (Mustela Vison) : Their Structural Similarity to Submammalian Pineal Complexes and Calcification*
    Arch. Histol. Cytol., Vol. 55, No. 5 (1992) p. 477-489 Two Components of the Pineal Organ in the Mink (Mustela vison) : Their Structural Similarity to Submammalian Pineal Complexes and Calcification* Bela VIGH and Ingeborg VIGH-TEICHMANN Photoneuroendocrine Laboratory of the Second Department of Anatomy, Histology and Embryology, Semmelweis University Medical School; and Neuroendocrine Section of the Hungarian Academy of Sciences, Semmelweis Medical University Joint Research Organization, Budapest, Hungary Received August 25, 1992 Summary. The pineal complex in the mink (Mustela The forerunner of vertebrates is believed to have vison) consists of a larger ventral and a smaller dorsal been four-eyed: two eyes looking laterally as locators pineal. Both organs contain pinealocytes, neurons, glial for perceiving the reflected light from objects in the cells, nerve fibers and synapses in an organization environment, and two eyes looking toward the sky characteristic of nervous tissue. The cellular elements as primitive pineal organs to perceive modifications are arranged circularly around strait lumina. These lumina correspond to the photoreceptor spaces of sub- of solar radiation (see Fig. 10, in VIGH and VIGH- mammalian pineals. A 9+0-type cilium marks the recep- TEICHMANN, 1988). Accordingly, two organs form a tory pole of the pinealocytes which may form an inner- pineal complex in some cyclostomes, teleosts, anur- segment-like dendrite terminal in the pineal lumina. ans and reptiles, while in other vertebrates they are The cilia correspond to outer segments which form photo- represented by a single organ or two anlages which receptor membrane multiplications in the pineal of sub- unite during ontogeny, as do the human pineal (MOL- mammalians and in certain insectivorous and mustelid LER, 1974).
    [Show full text]
  • Effects of Fluoridated Water on Pineal Morphology in Male Rats by Aaron
    Effects of Fluoridated Water on Pineal Morphology in Male Rats by Aaron Mrvelj Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Biological Sciences Program YOUNGSTOWN STATE UNIVERSITY August, 2017 Effects of Fluoridated Water on Pineal Morphology in Male Rats Aaron Mrvelj I hereby release this Thesis to the public. I understand that this thesis will be made available from the OhioLINK ETD Center and the Maag Library Circulation Desk for public access. I also authorize the University or other individuals to make copies of this thesis as needed for scholarly research. Signature: Aaron Mrvelj, Student Date Approvals: Dr. Mark Womble, Thesis Advisor Date Dr. Jill Tall, Committee Member Date Dr. Jeffrey Coldren, Committee Member Date Dr. Salvatore A. Sanders, Dean of Graduate Studies Date Abstract The pineal gland is a naturally calcifying endocrine organ which produ ces and releases the sleep-promoting hormone melatonin which also serves as an antioxidant. Fluoride is attracted to the calcium in the pineal gland and inhibits the synthesis and activity of melatonin, induces oxidative stress, and causes cellular changes to the neurons of the hippocampus. Morphological changes to the pineal gland have been demonstrated with increased age, exposure to light during a melatonin production period, or sleep deprivation. This study sought to examine the effects of fluoridated water on the morphology of the pineal gland. The effects of a fluoride-free flush were compared to fluoride treatment. Group 1, previously raised on fluoridated tap water served as a control that was sacrificed at the onset of the experiment.
    [Show full text]