Hypothalmo- Hypophysial Axis
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Expression Pattern of Delta-Like 1 Homolog in Developing Sympathetic Neurons and Chromaffin Cells
Published in "Gene Expression Patterns 30: 49–54, 2018" which should be cited to refer to this work. Expression pattern of delta-like 1 homolog in developing sympathetic neurons and chromaffin cells ∗ Tehani El Faitwria,b, Katrin Hubera,c, a Institute of Anatomy & Cell Biology, Albert-Ludwigs-University Freiburg, Albert-Str. 17, 79104, Freiburg, Germany b Department of Histology and Anatomy, Faculty of Medicine, Benghazi University, Benghazi, Libya c Department of Medicine, University of Fribourg, Route Albert-Gockel 1, 1700, Fribourg, Switzerland ABSTRACT Keywords: Delta-like 1 homolog (DLK1) is a member of the epidermal growth factor (EGF)-like family and an atypical notch Sympathetic neurons ligand that is widely expressed during early mammalian development with putative functions in the regulation Chromaffin cells of cell differentiation and proliferation. During later stages of development, DLK1 is downregulated and becomes DLK1 increasingly restricted to specific cell types, including several types of endocrine cells. DLK1 has been linked to Adrenal gland various tumors and associated with tumor stem cell features. Sympathoadrenal precursors are neural crest de- Organ of Zuckerkandl rived cells that give rise to either sympathetic neurons of the autonomic nervous system or the endocrine Development ffi Neural crest chroma n cells located in the adrenal medulla or extraadrenal positions. As these cells are the putative cellular Phox2B origin of neuroblastoma, one of the most common malignant tumors in early childhood, their molecular char- acterization is of high clinical importance. In this study we have examined the precise spatiotemporal expression of DLK1 in developing sympathoadrenal cells. We show that DLK1 mRNA is highly expressed in early sympa- thetic neuron progenitors and that its expression depends on the presence of Phox2B. -
I. Introduction B. Adrenal Cortex
I. Introduction Adrenal Glands • suprarenal – they sit on top of the kidneys • each is composed of 2 distinct regions: A. Adrenal Medulla - the inner region - comprises 20% of the gland - secretes epinephrine and norepinephrine - derived from ectoderm B. Adrenal Cortex 1) Zona Glomerulosa (outermost region) - produces mineralocorticoids (aldosterone) • the outer region 2) Zona Fasiculata (middle region) - produces glucocorticoids (cortisol) as well as • comprises 80% of the gland estrogens and androgens • secretes corticosteroids 3) Zona Reticularis (innermost region) • derived from mesoderm - same function as zona fasiculata DHEA – dehydroepiandrosterone • an adrenal androgen in females • responsible for growth of pubic and axillary hair C. Pathologies Associated with Adrenal II. Mineralocorticoids (Aldosterone) Androgen Hypersecretion A. Functions 1.Adrenogenital Syndrome - promotes reabsorption of Na+ and - hypersecretion of androgens or estrogens secretion of K+ from the distal portion of the a) in the adult female: nephron..primary regulator of salt balance and extracellular volume - masculinization (i.e. hirsutism) -Similar (but less important) effect on salt b) in the female embryo: transport in colon, salivary glands, and - female pseudohermaphroditism sweat glands. c) in the adult male: - no effect d) in young boys: - precocious pseudopuberty 1 II. Mineralocorticoids (Aldosterone) C. Pathologies B. Regulation of Secretion 1. Hypersecretion 1. Renin Angiotensin a. primary hyperaldosteronism - Angiotensin II stimulates aldost. secretion - Conn’s syndrome 2. Potassium - usually due to a tumor on the gland + - high levels of K induce aldost. secretion - too much secretion of gland itself 3. ACTH –no direct role b. secondary hyperaldosteronism - default in renin angiotensin system - most common in atherosclerosis of renal arteries C. Pathologies III. Glucocorticoids (Cortisol) 1. -
HYPOTHALAMUS – PITUITARY-ADRENAL AXIS Learning Objectives OVERVIEW FUNCTIONAL ANATOMY
Introductory Human Physiology ©copyright Emma Jakoi HYPOTHALAMUS – PITUITARY-ADRENAL AXIS Emma R. Jakoi, Ph.D. Learning objectives • Describe the structural and functional organization of the adrenal gland. • Describe the synthesis and secretion of cortical adrenal hormones. • Describe the mechanism of action and physiologic effects of adrenal hormones. • Explain the control of adrenal hormone synthesis and secretion. Describe the major feedback loops that integrate the hypothalamic axis and body homeostasis. • Explain the physiologic roles of the adrenal hormones in normal physiology. OVERVIEW The adrenal glands maintain homeostasis in response to stress. Three major classes of hormones are secreted by these glands: aldosterone (mineralocorticoid), cortisol (glucocorticoid), DHEA (weak androgen), and catecholamines (epinephrine and norepinephrine). FUNCTIONAL ANATOMY The adrenal gland is located on top of the kidney. Like the pituitary, two distinct tissues merge during development to form the adrenal cortex (glandular tissue) and medulla (modified neuronal tissue) (Fig 1). 1 2 cortex 3 medulla Figure 1. Structure of the adrenal gland. The cortex secretes three steroid hormones: 1. aldosterone, 2. cortisol, 3. a weak androgen, DHEA. The medulla secretes epinephrine (Epi) and norepinephrine (NorEpi). 1 Introductory Human Physiology ©copyright Emma Jakoi MINERALOCORTICOIDS The major mineralocorticoid in humans is aldosterone. Aldosterone is NOT under the hypothalamus- pituitary control and does not mediate a negative feedback to this axis. Aldosterone secretion is increased by the vasoconstrictor, angiotensin II, and by elevated plasma K+ concentration. Elevated plasma Na+ inhibits the secretion of aldosterone. Aldosterone, acts in the kidney to promote secretion of K+ into the urine from the blood and the reabsorption of Na+ from the urine into the blood. -
Beyond the Fixed Setpoint of the Hypothalamus–Pituitary–Thyroid Axis
E Fliers and others Hypothalamus–pituitary– 171:5 R197–R208 Review thyroid axis MECHANISMS IN ENDOCRINOLOGY Beyond the fixed setpoint of the hypothalamus–pituitary–thyroid axis Eric Fliers1, Andries Kalsbeek1,2 and Anita Boelen1 Correspondence should be addressed 1Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, 1105 AZ to E Fliers Amsterdam, The Netherlands and 2Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience, Email Amsterdam, The Netherlands e.fl[email protected] Abstract The hypothalamus–pituitary–thyroid (HPT) axis represents a classical example of an endocrine feedback loop. This review discusses dynamic changes in HPT axis setpoint regulation, identifying their molecular and cellular determinants, and speculates about their functional role. Hypothalamic thyrotropin-releasing hormone neurons were identified as key components of thyroid hormone (TH) setpoint regulation already in the 1980s, and this was followed by the demonstration of a pivotal role for the thyroid hormone receptor beta in negative feedback of TH on the hypothalamic and pituitary level. Gradually, the concept emerged of the HPT axis setpoint as a fixed entity, aiming at a particular TH serum concentration. However, TH serum concentrations appear to be variable and highly responsive to physiological and pathophysiological environmental factors, including the availability or absence of food, inflammation and clock time. During food deprivation and inflammation, TH serum concentrations decrease without a concomitant rise in serum TSH, reflecting a deviation from negative feedback regulation in the HPT axis. Surprisingly, TH action in peripheral organs in these conditions cannot be simply predicted by decreased serum TH concentrations. Instead, diverse environmental stimuli have differential effects on local TH metabolism, e.g. -
1-Anatomy of the Pituitary Gland
Color Code Important Anatomy of Pituitary Gland Doctors Notes Notes/Extra explanation Please view our Editing File before studying this lecture to check for any changes. Objectives At the end of the lecture, students should be able to: ✓ Describe the position of the pituitary gland. ✓ List the structures related to the pituitary gland. ✓ Differentiate between the lobes of the gland. ✓ Describe the blood supply of pituitary gland & the hypophyseal portal system. الغدة النخامية Pituitary Gland (also called Hypophysis Cerebri) o It is referred to as the master of endocrine glands. o It is a small oval structure 1 cm in diameter. o It doubles its size during pregnancy. lactation ,(الحمل) pregnancy ,(الحيض) A women experiences changes in her hormone levels during menstruation But only the pituitary gland will only increase in size during pregnancy .(سن اليأس) and menopause ,(الرضاعة) X-RAY SKULL: LATERAL VIEW SAGITTAL SECTION OF HEAD & NECK Extra Pituitary Gland Position o It lies in the middle cranial fossa. o It is well protected in sella turcica* (hypophyseal fossa) of body of sphenoid o It lies between optic chiasma (anteriorly) & mamillary bodies** (posteriorly). Clinical point: *سرج الحصان Anterior to the pituitary gland is the optic chiasm, so if there was a tumor in the pituitary gland or it was ** Part of hypothalamus enlarged this could press on the chiasm and disrupt the patients vision (loss of temporal field). Extra Pictures The purple part is the sphenoid bone Hypophyseal fossa Pituitary Gland The relations are important Important Relations • SUPERIOR: Diaphragma sellae: A fold of dura mater covers the pituitary gland & has an opening for passage of infundibulum (pituitary stalk) connecting the gland to hypothalamus. -
Study Guide Medical Terminology by Thea Liza Batan About the Author
Study Guide Medical Terminology By Thea Liza Batan About the Author Thea Liza Batan earned a Master of Science in Nursing Administration in 2007 from Xavier University in Cincinnati, Ohio. She has worked as a staff nurse, nurse instructor, and level department head. She currently works as a simulation coordinator and a free- lance writer specializing in nursing and healthcare. All terms mentioned in this text that are known to be trademarks or service marks have been appropriately capitalized. Use of a term in this text shouldn’t be regarded as affecting the validity of any trademark or service mark. Copyright © 2017 by Penn Foster, Inc. All rights reserved. No part of the material protected by this copyright may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the copyright owner. Requests for permission to make copies of any part of the work should be mailed to Copyright Permissions, Penn Foster, 925 Oak Street, Scranton, Pennsylvania 18515. Printed in the United States of America CONTENTS INSTRUCTIONS 1 READING ASSIGNMENTS 3 LESSON 1: THE FUNDAMENTALS OF MEDICAL TERMINOLOGY 5 LESSON 2: DIAGNOSIS, INTERVENTION, AND HUMAN BODY TERMS 28 LESSON 3: MUSCULOSKELETAL, CIRCULATORY, AND RESPIRATORY SYSTEM TERMS 44 LESSON 4: DIGESTIVE, URINARY, AND REPRODUCTIVE SYSTEM TERMS 69 LESSON 5: INTEGUMENTARY, NERVOUS, AND ENDOCRINE S YSTEM TERMS 96 SELF-CHECK ANSWERS 134 © PENN FOSTER, INC. 2017 MEDICAL TERMINOLOGY PAGE III Contents INSTRUCTIONS INTRODUCTION Welcome to your course on medical terminology. You’re taking this course because you’re most likely interested in pursuing a health and science career, which entails proficiencyincommunicatingwithhealthcareprofessionalssuchasphysicians,nurses, or dentists. -
Dream Recall/Affect and the Hypothalamic–Pituitary–Adrenal Axis
Review Dream Recall/Affect and the Hypothalamic–Pituitary–Adrenal Axis Athanasios Tselebis 1, Emmanouil Zoumakis 2 and Ioannis Ilias 3,* 1 Department of Psychiatry, Sotiria Hospital, 115 27 Athens, Greece; [email protected] 2 First Department of Pediatrics, National and Kapodistrian University of Athens Medical School, Aghia Sophia Children’s Hospital, 115 27 Athens, Greece; [email protected] 3 Department of Endocrinology, Diabetes and Metabolism, Elena Venizelou Hospital, 115 21 Athens, Greece * Correspondence: [email protected]; Tel.: +30-213-205-1389 Abstract: In this concise review, we present an overview of research on dream recall/affect and of the hypothalamic–pituitary–adrenal (HPA) axis, discussing caveats regarding the action of hormones of the HPA axis (mainly cortisol and its free form, cortisol-binding globulin and glucocorticoid receptors). We present results of studies regarding dream recall/affect and the HPA axis under physiological (such as waking) or pathological conditions (such as in Cushing’s syndrome or stressful situations). Finally, we try to integrate the effect of the current COVID-19 situation with dream recall/affect vis-à-vis the HPA axis. Keywords: dreams; cortisol; stress; memory; sleep; HPA axis 1. Introduction—Dream Recall Almost all humans dream (indeed, there may be 0.5% of people who do not do so) [1]. Dreams are a series of images, thoughts and senses and are considered a specific type Citation: Tselebis, A.; Zoumakis, E.; of experience that occurs in our brain during sleep. During the dream, there is limited Ilias, I. Dream Recall/Affect and the control of the dream content, visual images and memory activation. -
Pig Gonads, Adrenal Glands and Brain C
Immunoreactive cytochrome P-45017\g=a\in rat and guinea- pig gonads, adrenal glands and brain C. Le Goascogne1, N. Sanan\l=e'\s1, M. Gou\l=e'\zou1, S. Takemori2, S. Kominami2, E. E. Baulieu1 and P. Robel1 1INSERM U33, Communications Hormonales, and Faculté de Médecine, Université Paris-sud, Lab Hormones F-94275 Bicêtre Cedex France 2 Faculty of Integrated Arts and Sciences, Hiroshima University, Hiroshima 730, Japan Summary. The cytochrome P-45017\g=a\-hydroxylase, 17\ar=r\20lyase (P-45017\g=a\) is the key enzyme responsible for the biosynthesis of androgens in steroidogenic organs. Its cellular localization has been examined with an immunohistochemical technique. In immature rat ovary, P-45017\g=a\was first detected in sparse interstitial cells on postnatal Day 8. The number of immunoreactive interstitial cells increased thereafter and the intensity of P-45017\g=a\staining in these cells was highest at 3 weeks of age. The intensity of staining then started to decline and was very faint at Day 35. From 6 weeks on, the distribution of immunoreactive P-45017\g=a\was of the adult type: it was detected exclusively in the thecal cells of the large antral, preovulatory, follicles. P-45017\g=a\was not detectable during pregnancy except on the day of parturition, when thecal cells were transiently immunoreactive. The staining had vanished 24 h after delivery. Human chorionic gonadotrophin (hCG), injected into immature females on Days 24 to 26, induced P-45017\g=a\prematurely in thecal cells. When injected on Days 12 to 14 of pregnancy, hCG also induced P-45017\g=a\in the thecal cells surrounding the largest follicles, whereas the interstitial and luteal cells were not immunostained. -
Endocrinology Review – Adrenal and Thyroid Disorders
FOCUS: ENDOCRINOLOGY Endocrinology Review – Adrenal and Thyroid Disorders LINDA S. GORMAN, JANELLE M. CHIASERA LEARNING OBJECTIVES This article represents the first of three articles focusing 1. Define endocrinology and list the major endocrine on the endocrine system. The first article will provide glands of the body. you with fundamental theory regarding the endocrine system that will serve as a basis for understanding the 2. Explain how feedback (positive and negative) Downloaded from promotes maintenance of normal levels of next two articles focusing on two specific endocrine hormones. glands, the thyroid and adrenal glands. 3. Differentiate between steroid and peptide hormones with regard to their mechanism of Endocrinology is the branch of medical science that action. deals with the endocrine system, a system that consists 4. Provide examples of peptide and steroid hormones. of several glands located in different parts of the body http://hwmaint.clsjournal.ascls.org/ 5. Explain how endocrine disorders are categorized. that secrete hormones directly into the bloodstream. Although every organ system in the body may respond ABBREVIATIONS: ACTH - adrenocorticotropic hor- to hormones, endocrinology focuses specifically on mone; ADH - antidiuretic hormone; CRH – cortico- endocrine glands whose primary function is hormone tropin releasing hormone; DHEA – dehydroepian- secretion. Major endocrine glands include the pituitary drosterone; FSH - follicle stimulating hormone; GHRH (anterior and posterior), hypothalamus, thyroid, - growth hormone -
Adrenal Gland Hormones
CHAPTER 8 Adrenal Gland Hormones Devra K. Dang, PharmD, BCPS, CDE, FNAP | Trinh Pham, PharmD, BCOP | Jennifer J. Lee, PharmD, BCPS, CDE LEARNING OBJECTIVES KEY TERMS AND DEFINITIONS After completing this chapter, you should be able to ACTH (adrenocorticotropic hormone) — a hormone produced 1. Identify the hormones produced by the adrenal glands by the pituitary gland that stimulates 2. Describe the functions of mineralocorticoids and glucocorticoids in the body the adrenal cortex to produce glucocorticoids, mineralocorticoids, 3. Recognize the signs and symptoms of adrenal insuffi ciency and androgens. PART 4. Describe the pharmacological treatment of patients with acute and chronic adrenal Addison ’ s disease — a disorder insuffi ciency in which the adrenal glands do not produce enough steroid hormones. 3 5. Recognize the signs and symptoms of Cushing ’ s syndrome and the result of too Adenoma — a benign much cortisol (noncancerous) tumor of glandular 6. Describe the pharmacologic and nonpharmacologic management of patients with origin. Cushing ’ s syndrome Adrenal insuffi ciency — a term 7. List management strategies for administration of glucocorticoid and mineralocorti- referring to a defi ciency in the levels of adrenal hormones. coid therapy to avoid development of adrenal disorders Aldosterone — the hormone produced by the adrenal glands that regulates the balance of sodium, he adrenal glands are an integral part of the endocrine system, secreting water, and potassium concentrations in the body. T hormones that act throughout the body to regulate functions and promote Corticotropin-releasing homeostasis. In addition to the neurotransmitters epinephrine and norepineph- hormone (CRH) — a hormone rine, the corticosteroids secreted by the adrenal glands are vital to a wide released by the hypothalamus that variety of physiological processes. -
Thyroid and Polycystic Ovary Syndrome
S Gabersˇcˇek and others Thyroid and PCOS 172:1 R9–R21 Review MECHANISMS IN ENDOCRINOLOGY Thyroid and polycystic ovary syndrome Simona Gabersˇcˇek1,2, Katja Zaletel1, Verena Schwetz3, Thomas Pieber3, Barbara Obermayer-Pietsch3 and Elisabeth Lerchbaum3 Correspondence should be addressed to 1Department of Nuclear Medicine, University Medical Centre Ljubljana, Zalosˇka 7, 1525 Ljubljana, Slovenia, B Obermayer-Pietsch 2Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1104 Ljubljana, Slovenia and 3Division of Endocrinology Email and Metabolism, Department of Internal Medicine, Medical University of Graz, Auenbruggerplatz 15, barbara.obermayer@ 8036 Graz, Austria medunigraz.at Abstract Thyroid disorders, especially Hashimoto’s thyroiditis (HT), and polycystic ovary syndrome (PCOS) are closely associated, based on a number of studies showing a significantly higher prevalence of HT in women with PCOS than in controls. However, the mechanisms of this association are not as clear. Certainly, genetic susceptibility contributes an important part to the development of HT and PCOS. However, a common genetic background has not yet been established. Polymorphisms of the PCOS-related gene for fibrillin 3 (FBN3) could be involved in the pathogenesis of HT and PCOS. Fibrillins influence the activity of transforming growth factor beta (TGFb). Multifunctional TGFb is also a key regulator of immune tolerance by stimulating regulatory T cells (Tregs), which are known to inhibit excessive immune response. With lower TGFb and Treg levels, the autoimmune processes, well known in HT and assumed in PCOS, might develop. In fact, lower levels of TGFb1 were found in HT as well as in PCOS women carrying allele 8 of D19S884 in the FBN3 gene. -
Relation of the Anterior Pituitary to Ovarian Function
University of Nebraska Medical Center DigitalCommons@UNMC MD Theses Special Collections 5-1-1934 Relation of the anterior pituitary to ovarian function Clyde S. Martin University of Nebraska Medical Center This manuscript is historical in nature and may not reflect current medical research and practice. Search PubMed for current research. Follow this and additional works at: https://digitalcommons.unmc.edu/mdtheses Part of the Medical Education Commons Recommended Citation Martin, Clyde S., "Relation of the anterior pituitary to ovarian function" (1934). MD Theses. 621. https://digitalcommons.unmc.edu/mdtheses/621 This Thesis is brought to you for free and open access by the Special Collections at DigitalCommons@UNMC. It has been accepted for inclusion in MD Theses by an authorized administrator of DigitalCommons@UNMC. For more information, please contact [email protected]. e .,.,.~, THE RELATION OF THE ANTERIOR PITUITARY TO OVARIAN FUNCTION BY CLYDE S. MARTIN SE!HOR THESIS UNIVERSITY OF NEBRASKA SCHOOL OF MEDICINE APRIL I934 THE RELATIOM OF THE ANTERIOR PITUITARY TO OV ARIAJ.T FUNCTION !n ~be last ten years especially, there has been demonstrated and proved, a definite relationship between the pituitary and the sex glands. This is of importance to every clinician, and gynecologist. In order to understand these various phenomena produced by the internal secretion of the pituitary, it is advisable to give here a brief discussion of the anatomical structure, with slight reference to histology. ANATOMY A~TD HI~TOLOGY The pituitary body is situated in the cranium a.t the base of the brain, surrounded by a bony encasement the sella turcica.