Chapter 20: Endocrine System
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Distribution of Immunoreactive ,&Neo
0270-6474/84/0405-1248$02.00/O The Journal of Neuroscience Copyright 0 Society for Neuroscience Vol. 4, No. 5, pp. 1248-1252 Printed in U.S.A. May 1984 DISTRIBUTION OF IMMUNOREACTIVE ,&NEO-ENDORPHIN IN DISCRETE AREAS OF THE RAT BRAIN AND PITUITARY GLAND: COMPARISON WITH a-NEO-ENDORPHIN NADAV ZAMIR,’ MIKLOS PALKOVITS, AND MICHAEL J. BROWNSTEIN Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, Maryland 20205 Received August 5, 1983; Revised December 2, 1983; Accepted December 2, 1983 Abstract The distribution of immunoreactive (ir)-P-neo-endorphin in 101 miscrodissected rat brain and spinal cord regions as well as in the neurointermediate lobe of pituitary gland was determined using a highly specific radioimmunoassay. The highest concentration of P-neo-endorphin in brain was found in the median eminence (341.4 fmol/mg of protein). High concentrations of ir-/3-neo- endorphin (>250 fmol/mg of protein) were found in 11 nuclei, including dorsomedial nucleus, substantia nigra, parabrachial nuclei, periaqueductal gray matter, anterior hypothalamic nucleus, and lateral preoptic areas. Moderate concentrations of the peptide (between 100 and 250 fmol/mg of protein) were found in 66 brain nuclei such as the amygdaloid and septal nuclei, most of the diencephalic structures (not including the hypothalamus), and the majority of the medulla oblongata nuclei and others. Low concentrations of ir-P-neo-endorphin (Cl00 fmol/mg of protein) were found in 21 nuclei, e.g., cortical structures (frontal., cingulate, piriform, parietal, entorhinal, occipital), olfactory tubercle, and cerebellum (nuclei and cortex). The olfactory bulb has the lowest /3-neo- endorphin concentration (21.3 fmol/mg of protein). -
The Bright Pituitary Gland-A Normal MR Appearance in Infancy
The Bright Pituitary Gland-A Normal MR Appearance in Infancy Samuel M. Wolpert' Signal intensities of the pituitary gland were measured on T1 -weighted sagittal MR Mark Osborne2 images of 25 patients younger than 20 years old. We found that the signal intensities in Mary Anderson' the eight patients who were 8 weeks old or younger were higher (shorter T1) than those Val M. Runge2 in the 17 older patients. We also noted a difference in the signal intensities across the pituitary gland, the signal being higher in the posterior part of the gland than in the anterior part. We attribute the high signal intensities to the rapid intrauterine pituitary growth, so that at term pituitary protein synthetic activity is at a maximum. Possibly, an increase in the bound fraction of the water molecules of the gland may also be present in the neonatal pituitary as compared with the older gland, but this remains to be proved. The higher signal in the posterior pituitary gland may be due to lipid in the pituicyte cells of the posterior pituitary gland. The signal intensity of the contents of the sella turcica on T1-weighted MR images is not always uniform and homogeneous., Often , a high-intensity crescent shaped structure is seen oriented along the posterior-inferior margin of the sella turcica. Some believe this to be fat in the sella turcica but behind the gland [1]. Others think that the high intensity is derived from the posterior pituitary itself [2 , 3]. There are no published observations about the MR appearance of the pituitary gland in infants and children . -
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. -
Vocabulario De Morfoloxía, Anatomía E Citoloxía Veterinaria
Vocabulario de Morfoloxía, anatomía e citoloxía veterinaria (galego-español-inglés) Servizo de Normalización Lingüística Universidade de Santiago de Compostela COLECCIÓN VOCABULARIOS TEMÁTICOS N.º 4 SERVIZO DE NORMALIZACIÓN LINGÜÍSTICA Vocabulario de Morfoloxía, anatomía e citoloxía veterinaria (galego-español-inglés) 2008 UNIVERSIDADE DE SANTIAGO DE COMPOSTELA VOCABULARIO de morfoloxía, anatomía e citoloxía veterinaria : (galego-español- inglés) / coordinador Xusto A. Rodríguez Río, Servizo de Normalización Lingüística ; autores Matilde Lombardero Fernández ... [et al.]. – Santiago de Compostela : Universidade de Santiago de Compostela, Servizo de Publicacións e Intercambio Científico, 2008. – 369 p. ; 21 cm. – (Vocabularios temáticos ; 4). - D.L. C 2458-2008. – ISBN 978-84-9887-018-3 1.Medicina �������������������������������������������������������������������������veterinaria-Diccionarios�������������������������������������������������. 2.Galego (Lingua)-Glosarios, vocabularios, etc. políglotas. I.Lombardero Fernández, Matilde. II.Rodríguez Rio, Xusto A. coord. III. Universidade de Santiago de Compostela. Servizo de Normalización Lingüística, coord. IV.Universidade de Santiago de Compostela. Servizo de Publicacións e Intercambio Científico, ed. V.Serie. 591.4(038)=699=60=20 Coordinador Xusto A. Rodríguez Río (Área de Terminoloxía. Servizo de Normalización Lingüística. Universidade de Santiago de Compostela) Autoras/res Matilde Lombardero Fernández (doutora en Veterinaria e profesora do Departamento de Anatomía e Produción Animal. -
Shh/Gli Signaling in Anterior Pituitary
SHH/GLI SIGNALING IN ANTERIOR PITUITARY AND VENTRAL TELENCEPHALON DEVELOPMENT by YIWEI WANG Submitted in partial fulfillment of the requirements For the degree of Doctor of Philosophy Department of Genetics CASE WESTERN RESERVE UNIVERSITY January, 2011 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of _____________________________________________________ candidate for the ______________________degree *. (signed)_______________________________________________ (chair of the committee) ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ (date) _______________________ *We also certify that written approval has been obtained for any proprietary material contained therein. TABLE OF CONTENTS Table of Contents ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• i List of Figures ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• v List of Abbreviations •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• vii Acknowledgements •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• ix Abstract ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• x Chapter 1 Background and Significance ••••••••••••••••••••••••••••••••••••••••••••••••• 1 1.1 Introduction to the pituitary gland -
Chapter 45-Hormones and the Endocrine System Pathway Example – Simple Hormone Pathways Stimulus Low Ph in Duodenum
Chapter 45-Hormones and the Endocrine System Pathway Example – Simple Hormone Pathways Stimulus Low pH in duodenum •Hormones are released from an endocrine cell, S cells of duodenum travel through the bloodstream, and interact with secrete secretin ( ) Endocrine the receptor or a target cell to cause a physiological cell response Blood vessel A negative feedback loop Target Pancreas cells Response Bicarbonate release Insulin and Glucagon: Control of Blood Glucose Body cells •Insulin and glucagon are take up more Insulin antagonistic hormones that help glucose. maintain glucose homeostasis Beta cells of pancreas release insulin into the blood. The pancreas has clusters of endocrine cells called Liver takes islets of Langerhans up glucose and stores it as glycogen. STIMULUS: Blood glucose Blood glucose level level declines. rises. Target Tissues for Insulin and Glucagon Homeostasis: Blood glucose level Insulin reduces blood glucose levels by: (about 90 mg/100 mL) Promoting the cellular uptake of glucose Blood glucose STIMULUS: Slowing glycogen breakdown in the liver level rises. Blood glucose level falls. Promoting fat storage Alpha cells of pancreas release glucagon. Liver breaks down glycogen and releases glucose. Glucagon Glucagon increases blood glucose levels by: Stimulating conversion of glycogen to glucose in the liver Stimulating breakdown of fat and protein into glucose Diabetes Mellitus Type I diabetes mellitus (insulin-dependent) is an autoimmune disorder in which the immune system destroys pancreatic beta cells Type II diabetes -
Hypothalamus - Wikipedia
Hypothalamus - Wikipedia https://en.wikipedia.org/wiki/Hypothalamus The hypothalamus is a portion of the brain that contains a number of Hypothalamus small nuclei with a variety of functions. One of the most important functions of the hypothalamus is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamus is located below the thalamus and is part of the limbic system.[1] In the terminology of neuroanatomy, it forms the ventral part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is the size of an almond. The hypothalamus is responsible for the regulation of certain metabolic processes and other activities of the autonomic nervous system. It synthesizes and secretes certain neurohormones, called releasing hormones or hypothalamic hormones, Location of the human hypothalamus and these in turn stimulate or inhibit the secretion of hormones from the pituitary gland. The hypothalamus controls body temperature, hunger, important aspects of parenting and attachment behaviours, thirst,[2] fatigue, sleep, and circadian rhythms. The hypothalamus derives its name from Greek ὑπό, under and θάλαμος, chamber. Location of the hypothalamus (blue) in relation to the pituitary and to the rest of Structure the brain Nuclei Connections Details Sexual dimorphism Part of Brain Responsiveness to ovarian steroids Identifiers Development Latin hypothalamus Function Hormone release MeSH D007031 (https://meshb.nl Stimulation m.nih.gov/record/ui?ui=D00 Olfactory stimuli 7031) Blood-borne stimuli -
Biology F – Lesson 4 – Endocrine & Reproductive Systems
Unit: Biology F – Endocrine & Reproduction LESSON 4.1 - AN INTRODUCTION TO THE ENDOCRINE SYSTEM Overview: Students research the location and function of the major endocrine glands and consider some endocrine system disorders. Suggested Timeline: 1 hour Materials: • An Introduction to the Endocrine System (Student Handout) • QUIZ – The Endocrine System (Student Handout) • student access to computers with the internet Method: 1. Allow students to use computers with internet access and other resources from the library to complete their questions on the endocrine system. 2. Students write quiz on the endocrine system. Assessment and Evaluation: • Affective assessment of student understanding of parts of the endocrine system • Student grade on quiz Extension: Assign a student or group of students to ‘be’ a specific endocrine gland. Have them role play for the class to get the idea of the function of the gland across to their classmates. Science 21 Bio F – Endocrine B152 Unit: Biology F – Endocrine & Reproduction Student Handout Name: ______________ Partner(s): _________________________ Date: ____________ Period: _____ An Introduction to the Endocrine System Go to the following website: http://health.howstuffworks.com/adam-200091.htm Watch the video to complete the following questions. 1. The endocrine system is composed primarily of _________________ that produce chemical messengers called __________________. 2. List the names of glands of the endocrine system, as mentioned in the video. Hint: There are 8 in total. 3. The endocrine and ________________ systems work closely together. The brain sends info to the endocrine glands and the endocrine glands send feedback to the brain. 4. The part of the brain that is known as the ‘master switchboard’ and controls the endocrine system is called the _____________________. -
Avian Adrenal Medulla: Cytomorphology and Function
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Publications of the IAS Fellows Volume 45(1-4):1-11, 2001 Acta Biologica Szegediensis http://www.sci.u-szeged.hu/ABS REVIEW ARTICLE Avian adrenal medulla: cytomorphology and function Asok Ghosh, Stephen W. Carmichael1*, Monisha Mukherjee Department of Zoology, University of Calcutta, Calcutta, India, 1Department of Anatomy, Mayo Clinic/Foundation, Rochester, Minnesota, USA ABSTRACT The purpose of this review is to explore the world literature on the avian adrenal KEY WORDS medulla from the last 20 years. Unlike the mammalian adrenal medulla, the adrenal gland in adrenal medulla birds has chromaffin cells mixed with cortical cells. Studies have investigated the ultrastructure birds (both transmission and scanning electron microscopy), biochemistry, and physiology (partic- morphology ularly interactions with other endocrine glands) of the avian adrenal medulla. Although function progress has been made, it is apparent that research on the avian adrenal medulla still lags behind work on the mammalian organ. Acta Biol Szeged 45(1-4):1-11 (2001) The adrenal glands of birds, like those in mammals, are in the adrenal medulla. This profound variation of medullary paired yellow- or orange-colored pear- or triangle-shaped E/NE ratio in birds suggests a distinct evolutionary pattern glands that are next to the kidneys. The intermingling nature (Ghosh 1977, 1980). The avian phylogeny used in this study of cortical and medullary components constitutes a major was essentially based on palaeontological evidences (Grego- characteristic of avian adrenal medulla (Vestergaard and ry 1957). We feel that our “claim” of hormonal taxonomy is Willeberg 1978). -
Endocrine Tumors – Adrenal Medulla
Endocrine Tumors – Adrenal Medulla 803-808-7387 www.gracepets.com These notes are provided to help you understand the diagnosis or possible diagnosis of cancer in your pet. For general information on cancer in pets ask for our handout “What is Cancer”. Your veterinarian may suggest certain tests to help confirm or eliminate diagnosis, and to help assess treatment options and likely outcomes. Because individual situations and responses vary, and because cancers often behave unpredictably, science can only give us a guide. However, information and understanding for tumors in animals is improving all the time. We understand that this can be a very worrying time. We apologize for the need to use some technical language. If you have any questions please do not hesitate to ask us. What are the adrenal glands? The adrenal glands are located close to the kidneys. They are part of the body’s endocrine system, the glands of which also include the pituitary (in the brain), thyroid, parathyroid and Islets of Langerhans in the pancreas. Endocrine glands produce specialized chemicals called “hormones”. These regulate and integrate many activities to maintain internal stability of the body. The hormones pass directly into the blood to affect target cells elsewhere. Hormones are also produced by many cells in other tissues. Each of the two adrenal glands has two parts. The outer part (cortex) is controlled by a hormone (adrenocorticotrophic hormone, ACTH) from the pituitary gland. The cortex produces steroid hormones of several types. The inner part (medulla) of the adrenal gland originates from the same cells that in the embryo form the nervous system, and therefore not surprisingly it produces neuroendocrine hormones with effects similar to those of the sympathetic nervous system. -
Hypothalamushypothalamus -- Pituitarypituitary -- Adrenaladrenal Glandsglands
HypothalamusHypothalamus -- pituitarypituitary -- adrenaladrenal glandsglands Magdalena Gibas-Dorna MD, PhD Dept. of Physiology University of Medical Sciences Poznań, Poland Hypothalamus - general director of the hormone system. At every moment, the hypothalamus analyses messages coming from: the brain and different regions of the body. Homeostatic functions of hypothalamus include maintaining a stable body temperature, controlling food intake, controlling blood pressure, ensuring a fluid balance, and even proper sleep patterns. Cell bodies of neurons that produce releasing/inhibiting hormones Hypothalamus HypothalamusHypothalamus releases Arterial flow Primary capillaries in median eminence hormones at Long Releasing Portal hormones Anterior veins median eminence pituitary hormone Releasing/ inhibiting hormones and sends to anterior pituitary ANTERIOR PITUITARY via portalportal veinvein. Secretory cells that produce anterior pituitary hormones Anterior pituitary hormones Venous outflow Gonadotropic Thyroid- Proactin hormones stimulating ACTH Growth (FSH and LH) hormone hormone ControlControl ofof pituitarypituitary hormonehormone secretionsecretion byby hypothalamushypothalamus • Secretion by the anterioranterior pituitarypituitary is controlled by hormones called hypothalamic releasing hormones and inhibitory hormones conducted to the anterior pituitary through hypothalamichypothalamic -- hypophysialhypophysial portalportal vesselsvessels .. • PosteriorPosterior pituitarypituitary secrets two hormones, which are synthesized within cell -
The Endocrine System
4/12/2016 Adrenal Glands Image From: http://www.hawaiilife.com/articles/2012/03/good-news-vacation-rental-owners/ 70 Copyright © 2009 Pearson Education, Inc Figure 10.14a Adrenal Glands Adrenal Adrenal cortex Adrenal Glands gland • Mineralocorticoids • Gonadocorticoids • Glucocorticoids • Controlled by both nerves and hormones – Adrenal medulla Adrenal Medulla • Epinephrine • Controlled by nerves from the hypothalamus • Norepinephrine – Adrenal Cortex • Controlled by ACTH (a hormone) secreted by the anterior pituitary gland (b) A section through the adrenal gland reveals two regions, the outer adrenal cortex and the inner adrenal medulla. These regions secrete different hormones. 73 Copyright © 2009 Pearson Education, Inc Figure 10.14b Adrenal Glands Adrenal Glands • Adrenal Medulla • Adrenal Cortex – Epinephrine – 2 types of hormones secreted • Increases blood pressure • Mineralocorticoids • Increases heart rate • Glucocorticoids • Increases blood glucose levels 74 Copyright © 2009 Pearson Education, Inc 75 Copyright © 2009 Pearson Education, Inc 1 4/12/2016 Adrenal Glands - Cortex Adrenal Glands - Cortex • Mineralocorticoids • Aldosterone – Example: Aldosterone – Promotes renal absorption of Na+ and renal – Mineral homeostasis excretion of K+ – Water balance – Increased blood pressure • Target – Kidneys 76 Copyright © 2009 Pearson Education, Inc 77 Copyright © 2009 Pearson Education, Inc Adrenal Glands - Cortex Adrenal Glands - Cortex • Glucocorticoids • Cortisol – Example: Cortisol – Effects glucose homeostasis – Act on the liver to