I AMYLIN MEDIATES BRAINSTEM

Total Page:16

File Type:pdf, Size:1020Kb

I AMYLIN MEDIATES BRAINSTEM AMYLIN MEDIATES BRAINSTEM CONTROL OF HEART RATE IN THE DIVING REFLEX A Dissertation Submitted to The Temple University Graduate Board In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy By Fan Yang May, 2012 Examination committee members: Dr. Nae J Dun (advisor), Dept. of Pharmacology, Temple University Dr. Alan Cowan, Dept. of Pharmacology, Temple University Dr. Lee-Yuan Liu-Chen, Dept. of Pharmacology, Temple University Dr. Gabriela Cristina Brailoiu, Dept. of Pharmacology, Temple University Dr. Parkson Lee-Gau Chong, Dept. of Biochemistry, Temple University Dr. Hreday Sapru (external examiner), Depts. of Neurosciences, Neurosurgery & Pharmacology/Physiology, UMDNJ-NJMS. i © 2012 By Fan Yang All Rights Reserved ii ABSTRACT AMYLIN’S ROLE AS A NEUROPEPTIDE IN THE BRAINSTEM Fan Yang Doctor of Philosophy Temple University, 2012 Doctoral Advisory Committee Chair: Nae J Dun, Ph.D. Amylin, or islet amyloid polypeptide is a 37-amino acid member of the calcitonin peptide family. Amylin role in the brainstem and its function in regulating heart rates is unknown. The diving reflex is a powerful autonomic reflex, however no neuropeptides have been described to modulate its function. In this thesis study, amylin expression in the brainstem involving pathways between the trigeminal ganglion and the nucleus ambiguus was visualized and characterized using immunohistochemistry. Its functional role in slowing heart rate and also its involvement in the diving reflex were elucidated using stereotaxic microinjection, whole-cel patch-clamp, and a rat diving model. Immunohistochemical and tract tracing studies in rats revealed amylin expression in trigeminal ganglion cells, which also contained vesicular glutamate transporter 2 positive. With respect to the brainstem, amylin containing fibers were discovered in spinal trigeminal tracts. These fibers curved dorsally toward choline acetyltransferase immunoreactive neurons of the nucleus ambiguus, suggesting that amylin may synapse to parasympathetic preganglionic neurons in the nucleus ambiguus. Microinjection of fluorogold to the nucleus ambiguus retrogradely labeled a population of trigeminal ganglion neurons; some of which also contained amylin. In urethane-anesthetized rats, stereotaxic microinjections of amylin to the nucleus ambiguus caused a dose-dependent iii bradycardia that was reversibly attenuated by microinjections of the selective amylin receptor antagonist, salmon calcitonin (8-32) (sCT (8-32)) or AC187, and abolished by bilateral vagotomy. In an anesthetized rat diving model, diving bradycardia was attenuated by glutamate receptor antagonists CNQX and AP5, and was further suppressed by AC187. Whole-cel patch-clamp recordings from cardiac preganglionic vagal neurons revealed that amylin depolarizes neurons while decreasing conductance. Amylin also resulted in a reduction in whole cell currents, consistent with the decrease in conductance. Amylin is also found to increase excitability of neurons. In the presence of TTX, spontaneous currents in cardiac preganglionic vagal neurons were observed to decrease in frequency in response to amylin while amplitude remained constant, signifying that amylin reduces presynaptic activity at cardiac preganglionic vagal neurons. Finally, evoked synaptic currents revealed that amylin decreases evoked currents, further demonstrating that amylin depolarization and increase in excitability of cardiac preganglionic vagal neurons is also associated with simultaneous inhibition of presynaptic transmission. Our study has demonstrated for the first time that the bradycardia elicited by the diving reflex is mediated by amylin from trigeminal ganglion cells projecting to cardiac preganglionic neurons in the nucleus ambiguus. Additionally, amylin results in the depolarization and increased excitability of cardiac preganglionic vagal neurons while inhibiting presynaptic transmission. iv DEDICATION I would like to dedicate this thesis to my family, who without their endless love and support, this day would not be possible. To my loving wife and best friend Irene Hwa Yang, thank you for supporting me and walking by my side through this journey. To my parents, who I have the highest respect for, thank you for the never ending love and enthusiasm. To my brother, in whom I see myself, you have taught me more about myself and about life than anyone else. Thank you. v ACKNOWLEDGEMENTS I would like to thank everyone who has made helped make my thesis work possible through supporting my professional development and personal growth. I would like to thank my PhD mentor Dr. Nae Dun. Through his thoughtful guidance in my thesis work, he has helped open my mind to science. Dr. Dun has exposed me to a depth of scientific thinking that has made a lasting impact in my life. His unwavering support in my work has given me the ability to develop my intellectual capability immensely. Most of all, as a mentor, Dr. Dun has helped me think out of the box and apply what I have learned not only to furthering scientific knowledge, but also to all areas of life. The members of the Dun lab have provided a nurturing and supportive environment in which I have spent some of the most memorable years of my life. I want to thank Mrs. Siok Le Dun for the patience in teaching me immunohistochemistry and helping me navigate through the immense resources available in the Dun Lab. Without her patience, guidance, and support, none of my experiments would be possible. I also want to thank Dr. Cristina Brailoiu, for serving my PhD committee, and also helping me learn electrophysiology. It is the most technically challenging scientific tool I have ever mastered and it would not have been possible without her help. I want to thank my fellow PhD students in the Dun Lab whom have taken the quest for science together- Saadet Inan, Xiaofang Huang, and Elena Deliu. Through countless failed experiments we persevered while building lifelong friendships. I want to thank my thesis committee members for providing me with thoughtful feedback over the years and helping nurture my love for science. vi TABLE OF CONTENTS Pages ABSTRACT .................................................................................................................................... iii DEDICATION ................................................................................................................................. v ACKNOWLEDGEMENTS ............................................................................................................ vi LIST OF FIGURES: ........................................................................................................................ x LIST OF ABBREVIATIONS ................................................................................................................. xi CHAPTER 1: INTRODUCTION ............................................................................................................ 1 1.1 Importance of neural control of heart rate: .......................................................................... 1 1.2 Organization of the nervous system: ..................................................................................... 2 1.3 Autonomic Nervous System ................................................................................................... 3 1.3.1 Somatic Reflexes ............................................................................................................. 4 1.3.2 Autonomic Reflexes ........................................................................................................ 4 1.3.3 Baroreceptor reflex ......................................................................................................... 5 1.4 Information transmission and processing ............................................................................. 7 1.4.1 Excitable membranes ...................................................................................................... 7 1.4.2 Membrane permeability ................................................................................................. 8 1.5 Synapse ................................................................................................................................ 12 1.6 Neurotransmitters ............................................................................................................... 13 1.7 Ionotropic and Metabotropic receptors .............................................................................. 15 1.8 Neuropeptides ..................................................................................................................... 18 1.9 Neuropeptide synthesis and processing .............................................................................. 21 1.10 Neuropeptide Receptors .................................................................................................... 23 1.11 Amylin: ............................................................................................................................... 24 1.11.1 Circulating amylin ....................................................................................................... 24 1.11.2 Amylin the neuropeptide ............................................................................................ 27 Amylin action on neurons ...................................................................................................... 29 1.11.3 Amylin Genetics .........................................................................................................
Recommended publications
  • Searching for Novel Peptide Hormones in the Human Genome Olivier Mirabeau
    Searching for novel peptide hormones in the human genome Olivier Mirabeau To cite this version: Olivier Mirabeau. Searching for novel peptide hormones in the human genome. Life Sciences [q-bio]. Université Montpellier II - Sciences et Techniques du Languedoc, 2008. English. tel-00340710 HAL Id: tel-00340710 https://tel.archives-ouvertes.fr/tel-00340710 Submitted on 21 Nov 2008 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITE MONTPELLIER II SCIENCES ET TECHNIQUES DU LANGUEDOC THESE pour obtenir le grade de DOCTEUR DE L'UNIVERSITE MONTPELLIER II Discipline : Biologie Informatique Ecole Doctorale : Sciences chimiques et biologiques pour la santé Formation doctorale : Biologie-Santé Recherche de nouvelles hormones peptidiques codées par le génome humain par Olivier Mirabeau présentée et soutenue publiquement le 30 janvier 2008 JURY M. Hubert Vaudry Rapporteur M. Jean-Philippe Vert Rapporteur Mme Nadia Rosenthal Examinatrice M. Jean Martinez Président M. Olivier Gascuel Directeur M. Cornelius Gross Examinateur Résumé Résumé Cette thèse porte sur la découverte de gènes humains non caractérisés codant pour des précurseurs à hormones peptidiques. Les hormones peptidiques (PH) ont un rôle important dans la plupart des processus physiologiques du corps humain.
    [Show full text]
  • Features of Hemodynamics of Pulmonary Circulation During the Diving Reflex
    FULL COMMUNICATIONS PHYSIOLOGY Features of hemodynamics of pulmonary circulation during the diving reflex Ekaterina Podyacheva1, Tatyana Zemlyanukhina1, Lavrentij Shadrin2, and Tatyana Baranova1 1Department of General Physiology, Faculty of Biology, Saint Petersburg State University, Universitetskaya nab., 7–9, Saint Petersburg, 199034, Russian Federation 2Department of Physical Culture and Sports, Saint Petersburg State University, Universitetskaya nab., 7–9, Saint Petersburg, 199034, Russian Federation Address correspondence and requests for materials to Ekaterina Podyacheva, [email protected] Abstract The adaptive cardiovascular reactions of the human diving reflex were studied. The diving reflex was activated by submerging a face in cold water under labo- ratory conditions. Forty volunteers (aged 18–24) were examined. ECG, arterial blood pressure (ABP) and central blood flow were recorded by the impedance rheography method in resting state, during diving simulation (DS) and after apnea. During DS there is a statistically significant decrease in the dicrotic in- dex (DCI), which reflects a decrease in the resistive vessel tone and as well as diastolic index (DSI), characterizing lung perfusion. A comparison of the latent periods (LP) of an increase in ABP and a drop in DCI showed that a decrease in pulmonary vascular tone develops faster than ABP begins to increase. The LP for lowering DCI is from 0.6 to 10 s; for an increase in ABP — from 6 to 30 s. A short LP for DCI and the absence of a correlation between a decrease in ABP and DCI suggests that a decrease in pulmonary vascular tone during DS occurs reflexively and independently of a change in ABP. Keywords: diving reflex, systemic circulation, pulmonary circulation, impedan- ce rheography, plethysmography.
    [Show full text]
  • Effects of Β-Lipotropin and Β-Lipotropin-Derived Peptides on Aldosterone Production in the Rat Adrenal Gland
    Effects of β-Lipotropin and β-Lipotropin-derived Peptides on Aldosterone Production in the Rat Adrenal Gland Hiroaki Matsuoka, … , Patrick J. Mulrow, Roberto Franco-Saenz J Clin Invest. 1981;68(3):752-759. https://doi.org/10.1172/JCI110311. Research Article To investigate the role of non-ACTH pituitary peptides on steroidogenesis, we studied the effects of synthetic β-lipotropin, β-melanotropin, and β-endorphin on aldosterone and corticosterone stimulation using rat adrenal collagenase-dispersed capsular and decapsular cells. β-lipotropin induced a significant aldosterone stimulation in a dose-dependent fashion (10 nM-1 μM). β-endorphin, which is the carboxyterminal fragment of β-lipotropin, did not stimulate aldosterone production at the doses used (3 nM-6 μM). β-melanotropin, which is the middle fragment of β-lipotropin, showed comparable effects on aldosterone stimulation. β-lipotropin and β-melanotropin did not affect corticosterone production in decapsular cells. Although ACTH1-24 caused a significant increase in cyclic AMP production in capsular cells in a dose-dependent fashion (1 nM-1 μM), β-lipotropin and β-melanotropin did not induce an increase in cyclic AMP production at the doses used (1 nM-1 μM). The β-melanotropin analogue (glycine[Gly]10-β-melanotropin) inhibited aldosterone production induced by β- lipotropin or β-melanotropin, but did not inhibit aldosterone production induced by ACTH1-24 or angiotensin II. Corticotropin-inhibiting peptide (ACTH7-38) inhibited not only ACTH1-24 action but also β-lipotropin or β-melanotropin action; however it did not affect angiotensin II-induced aldosterone production. (saralasin [Sar]1; alanine [Ala]8)- Angiotensin II inhibited the actions of β-lipotropin and β-melanotropin as well as angiotensin II.
    [Show full text]
  • Minnesota Ttaps Part 1
    MINNESOTA TTAPS PART 1 COURSE NAME: USE OF REFLEXES TO RESOLVE BIOMECHANICS OF CHRONIC NEURO-MUSCULAR-SKELETAL DIAGNOSES COURSE COORDINATOR: ALAN R. BONEBRAKE, DC 630C N CENTRAL EXPY PLANO, TX 75074 COURSE DESCRIPTION: P.A.C.E APPROVED 16 CEs USE OF MYOTATIC, POSTURAL, RECIPROCAL, WITHDRAWAL, AND CROSSED EXTENSOR REFLEXES TO RESOLVE PAIN AND BIOMECHANICS OF CHRONIC NEURO-MUSCULAR- SKELETAL CONDITIONS EDUCATIONAL OBJECTIVES: DISCUSSION OF NORMAL FUNCTION OF MYOTATIC REFLEXES DISCUSSION OF CAUSES OF FACILITATED NERVES RELATING TO WITHDRAWAL REFLEXES CAUSING CHRONIC NEURO-MUSCULAR-SKELETAL CONDITIONS DISCUSSION OF VARIETIES OF WITHDRAWAL REFLEXES DISCUSSION OF AND WORKSHOP OF REINSTATING NORMOTONUS OF HYPERTONIC NERVES AND MUSCLES THROUGH REFLEX INHIBITION UTILIZING MYOTATIC REFLEXES TEACHING METHODS: VERBAL, OVERHEAD PROJECTOR, HANDOUT OF COURSE OUTLINE AND POSSIBLY THE OVERHEADS THAT AREN’T COPYRIGHTED, INSTRUCTOR WATCHING AND CRITIQUING THE STUDENTS PERFORMING THE TREATMENTS RECOMMENDED READING: GUYTON’S TEXTBOOK OF MEDICAL PHYSIOLOGY, 5TH & 9TH ED.; CHUSID’S CORRELATIVE NEUROANATOMY AND FUNCTIONAL NEUROLOGY; MAZION’S ILLUSTRATED MANUAL OF NEURO/ ORTHO/PHYSIOLOGICAL TESTS; THE CHALLENGE OF PAIN BY MELZACK; AND WALL; ACUPUNCTURE, THE ANCIENT CHINESE ART OF HEALING AND HOW IT WORKS SCIENTIFICALLY BY FELIX MANN, MB; CUNNINGHAM’S TEXTBOOK OF ANATOMY, 11TH ED; DORLAND’S ILLUSTRATED MEDICAL DICTIONARY, 25TH ED ~ 1 ~ st 1 hour: All-or-none law The all-or-none law is the principle that the strength by which a nerve or muscle fiber responds to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential, the nerve or muscle fiber will give a complete response; otherwise, there is no response.
    [Show full text]
  • Lipotropin, Melanotropin and Endorphin: in Vivo Catabolism and Entry Into Cerebrospinal Fluid
    LE JOURNAL CANAD1EN DES SCIENCES NEUROLOGIQUES Lipotropin, Melanotropin and Endorphin: In Vivo Catabolism and Entry into Cerebrospinal Fluid P. D. PEZALLA, M. LIS, N. G. SEIDAH AND M. CHRETIEN SUMMARY: Anesthetized rabbits were INTRODUCTION (Rudman et al., 1974). These findings given intravenous injections of either Beta-lipotropin (beta-LPH) is a suggest, albeit weakly, that the pep­ beta-lipotropin (beta-LPH), beta- peptide of 91 amino acids that was tide might cross the blood-brain bar­ melanotropin (beta-MSH) or beta- first isolated from ovine pituitary rier. In the case of beta-endorphin, endorphin. The postinjection concentra­ glands (Li et al., 1965). Although there are physiological studies both tions of these peptides in plasma and cerebrospinal fluid (CSF) were measured beta-LPH has a number of physiologi­ supporting and negating the possibil­ by radioimmunoassay (RIA). The plasma cal actions including the stimulation ity that beta-endorphin crosses the disappearance half-times were 13.7 min of lipolysis and melanophore disper­ blood-brain barrier. The study of for beta-LPH, 5.1 min for beta-MSH, and sion, it is believed to function princi­ Tseng et al. (1976) supports this pos­ 4.8 min for beta-endorphin. Circulating pally as a prohormone for beta- sibility since they observed analgesia beta-LPH is cleaved to peptides tenta­ melanotropin (beta-MSH) and beta- in mice following intravenous injec­ tively identified as gamma-LPH and endorphin. Beta-MSH, which com­ tion of beta-endorphin. However, beta-endorphin. Each of these peptides prises the sequence 41-58 of beta- Pert et al. (1976) were unable to elicit appeared in the CSF within 2 min postin­ LPH, is considerably more potent central effects in rats by intravenous jection.
    [Show full text]
  • Neurotransmitter and Neuropeptide Regulation of Mast Cell Function
    Xu et al. Journal of Neuroinflammation (2020) 17:356 https://doi.org/10.1186/s12974-020-02029-3 REVIEW Open Access Neurotransmitter and neuropeptide regulation of mast cell function: a systematic review Huaping Xu1, Xiaoyun Shi2, Xin Li3, Jiexin Zou4, Chunyan Zhou5, Wenfeng Liu5, Huming Shao5, Hongbing Chen5 and Linbo Shi4* Abstract The existence of the neural control of mast cell functions has long been proposed. Mast cells (MCs) are localized in association with the peripheral nervous system (PNS) and the brain, where they are closely aligned, anatomically and functionally, with neurons and neuronal processes throughout the body. They express receptors for and are regulated by various neurotransmitters, neuropeptides, and other neuromodulators. Consequently, modulation provided by these neurotransmitters and neuromodulators allows neural control of MC functions and involvement in the pathogenesis of mast cell–related disease states. Recently, the roles of individual neurotransmitters and neuropeptides in regulating mast cell actions have been investigated extensively. This review offers a systematic review of recent advances in our understanding of the contributions of neurotransmitters and neuropeptides to mast cell activation and the pathological implications of this regulation on mast cell–related disease states, though the full extent to which such control influences health and disease is still unclear, and a complete understanding of the mechanisms underlying the control is lacking. Future validation of animal and in vitro models also is needed, which incorporates the integration of microenvironment-specific influences and the complex, multifaceted cross-talk between mast cells and various neural signals. Moreover, new biological agents directed against neurotransmitter receptors on mast cells that can be used for therapeutic intervention need to be more specific, which will reduce their ability to support inflammatory responses and enhance their potential roles in protecting against mast cell–related pathogenesis.
    [Show full text]
  • A G-Protein-Coupled Receptor Mediates Neuropeptide-Induced
    bioRxiv preprint doi: https://doi.org/10.1101/801225; this version posted October 10, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. A G-protein-coupled receptor mediates neuropeptide-induced oocyte maturation in the jellyfish Clytia Gonzalo Quiroga Artigas1#, Pascal Lapébie1, Lucas Leclère1, Philip Bauknecht 2, Julie Uveira1, Sandra Chevalier1, Gáspár Jékely2,3, Tsuyoshi Momose1 and Evelyn Houliston1* 1. Sorbonne University, CNRS, Villefranche-sur-mer Developmental Biology Laboratory (LBDV), 06230 Villefranche-sur-mer, France 2. Max Planck Institute for Developmental Biology, Spemannstraße 35, 72076 Tübingen, Germany. 3. Living Systems Institute, University of Exeter, Stocker Road, EX4 4QD, Exeter, UK # current address: GQA: The Whitney Laboratory for Marine Bioscience, University of Florida, St. Augustine, FL, USA *Corresponding author: E. Houliston [email protected] Short title: The Clytia oocyte maturation hormone receptor 1 bioRxiv preprint doi: https://doi.org/10.1101/801225; this version posted October 10, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Abstract The reproductive hormones that trigger oocyte meiotic maturation and release from the ovary vary greatly between animal species. Identification of receptors for these Maturation Inducing Hormones (MIHs), and understanding how they initiate the largely conserved maturation process, remain important challenges.
    [Show full text]
  • A 0.70% E 0.80% Is 0.90%
    US 20080317666A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2008/0317666 A1 Fattal et al. (43) Pub. Date: Dec. 25, 2008 (54) COLONIC DELIVERY OF ACTIVE AGENTS Publication Classification (51) Int. Cl. (76) Inventors: Elias Fattal, Paris (FR); Antoine A6IR 9/00 (2006.01) Andremont, Malakoff (FR); A61R 49/00 (2006.01) Patrick Couvreur, A6II 5L/12 (2006.01) Villebon-sur-Yvette (FR); Sandrine A6IPI/00 (2006.01) Bourgeois, Lyon (FR) (52) U.S. Cl. .......................... 424/1.11; 424/423; 424/9.1 (57) ABSTRACT Correspondence Address: Drug delivery devices that are orally administered, and that David S. Bradlin release active ingredients in the colon, are disclosed. In one Womble Carlyle Sandridge & Rice embodiment, the active ingredients are those that inactivate P.O.BOX 7037 antibiotics, such as macrollides, quinolones and beta-lactam Atlanta, GA 30359-0037 (US) containing antibiotics. One example of a Suitable active agent is an enzyme Such as beta-lactamases. In another embodi ment, the active agents are those that specifically treat colonic (21) Appl. No.: 11/628,832 disorders, such as Chrohn's Disease, irritable bowel syn drome, ulcerative colitis, colorectal cancer or constipation. (22) PCT Filed: Feb. 9, 2006 The drug delivery devices are in the form of beads of pectin, crosslinked with calcium and reticulated with polyethylene imine. The high crosslink density of the polyethyleneimine is (86). PCT No.: PCT/GBO6/OO448 believed to stabilize the pectin beads for a sufficient amount of time such that a Substantial amount of the active ingredi S371 (c)(1), ents can be administered directly to the colon.
    [Show full text]
  • Targeting Neuropeptide Receptors for Cancer Imaging and Therapy: Perspectives with Bombesin, Neurotensin, and Neuropeptide-Y Receptors
    Journal of Nuclear Medicine, published on September 4, 2014 as doi:10.2967/jnumed.114.142000 CONTINUING EDUCATION Targeting Neuropeptide Receptors for Cancer Imaging and Therapy: Perspectives with Bombesin, Neurotensin, and Neuropeptide-Y Receptors Clément Morgat1–3, Anil Kumar Mishra2–4, Raunak Varshney4, Michèle Allard1,2,5, Philippe Fernandez1–3, and Elif Hindié1–3 1CHU de Bordeaux, Service de Médecine Nucléaire, Bordeaux, France; 2University of Bordeaux, INCIA, UMR 5287, Talence, France; 3CNRS, INCIA, UMR 5287, Talence, France; 4Division of Cyclotron and Radiopharmaceutical Sciences, Institute of Nuclear Medicine and Allied Sciences, DRDO, New Delhi, India; and 5EPHE, Bordeaux, France Learning Objectives: On successful completion of this activity, participants should be able to list and discuss (1) the presence of bombesin receptors, neurotensin receptors, or neuropeptide-Y receptors in some major tumors; (2) the perspectives offered by radiolabeled peptides targeting these receptors for imaging and therapy; and (3) the choice between agonists and antagonists for tumor targeting and the relevance of various PET radionuclides for molecular imaging. Financial Disclosure: The authors of this article have indicated no relevant relationships that could be perceived as a real or apparent conflict of interest. CME Credit: SNMMI is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing education for physicians. SNMMI designates each JNM continuing education article for a maximum of 2.0 AMA PRA Category 1 Credits. Physicians should claim only credit commensurate with the extent of their participation in the activity. For CE credit, SAM, and other credit types, participants can access this activity through the SNMMI website (http://www.snmmilearningcenter.org) through October 2017.
    [Show full text]
  • Near Drowning
    Near Drowning McHenry Western Lake County EMS Definition • Near drowning means the person almost died from not being able to breathe under water. Near Drownings • Defined as: Survival of Victim for more than 24* following submission in a fluid medium. • Leading cause of death in children 1-4 years of age. • Second leading cause of death in children 1-14 years of age. • 85 % are caused from falls into pools or natural bodies of water. • Male/Female ratio is 4-1 Near Drowning • Submersion injury occurs when a person is submerged in water, attempts to breathe, and either aspirates water (wet) or has laryngospasm (dry). Response • If a person has been rescued from a near drowning situation, quick first aid and medical attention are extremely important. Statistics • 6,000 to 8,000 people drown each year. Most of them are within a short distance of shore. • A person who is drowning can not shout for help. • Watch for uneven swimming motions that indicate swimmer is getting tired Statistics • Children can drown in only a few inches of water. • Suspect an accident if you see someone fully clothed • If the person is a cold water drowning, you may be able to revive them. Near Drowning Risk Factor by Age 600 500 400 300 Male Female 200 100 0 0-4 yr 5-9 yr 10-14 yr 15-19 Ref: Paul A. Checchia, MD - Loma Linda University Children’s Hospital Near Drowning • “Tragically 90% of all fatal submersion incidents occur within ten yards of safety.” Robinson, Ped Emer Care; 1987 Causes • Leaving small children unattended around bath tubs and pools • Drinking
    [Show full text]
  • Identification of Neuropeptide Receptors Expressed By
    RESEARCH ARTICLE Identification of Neuropeptide Receptors Expressed by Melanin-Concentrating Hormone Neurons Gregory S. Parks,1,2 Lien Wang,1 Zhiwei Wang,1 and Olivier Civelli1,2,3* 1Department of Pharmacology, University of California Irvine, Irvine, California 92697 2Department of Developmental and Cell Biology, University of California Irvine, Irvine, California 92697 3Department of Pharmaceutical Sciences, University of California Irvine, Irvine, California 92697 ABSTRACT the MCH system or demonstrated high expression lev- Melanin-concentrating hormone (MCH) is a 19-amino- els in the LH and ZI, were tested to determine whether acid cyclic neuropeptide that acts in rodents via the they are expressed by MCH neurons. Overall, 11 neuro- MCH receptor 1 (MCHR1) to regulate a wide variety of peptide receptors were found to exhibit significant physiological functions. MCH is produced by a distinct colocalization with MCH neurons: nociceptin/orphanin population of neurons located in the lateral hypothala- FQ opioid receptor (NOP), MCHR1, both orexin recep- mus (LH) and zona incerta (ZI), but MCHR1 mRNA is tors (ORX), somatostatin receptors 1 and 2 (SSTR1, widely expressed throughout the brain. The physiologi- SSTR2), kisspeptin recepotor (KissR1), neurotensin cal responses and behaviors regulated by the MCH sys- receptor 1 (NTSR1), neuropeptide S receptor (NPSR), tem have been investigated, but less is known about cholecystokinin receptor A (CCKAR), and the j-opioid how MCH neurons are regulated. The effects of most receptor (KOR). Among these receptors, six have never classical neurotransmitters on MCH neurons have been before been linked to the MCH system. Surprisingly, studied, but those of most neuropeptides are poorly several receptors thought to regulate MCH neurons dis- understood.
    [Show full text]
  • Model Document: Review Paper
    6186ch05.qxd_lb 1/13/06 12:57 PM Page 130 130 5 / Writing a Review Paper Include title, author, course, The Role of Hypothermia and the Diving and date on title page for Reflex in Survival of Near-Drowning student papers. Accidents Do not number title page, but consider it page 1. Brian Martin Biology 281 April 17, 200- 6186ch05.qxd_lb 1/13/06 12:57 PM Page 131 Sample Review Paper 131 Hypothermia and the Diving Reflex 2 ABSTRACT State aims and scope; concisely This paper reviews the contributions summarize of hypothermia and the mammalian diving major points. reflex (MDR) to human survival of cold- water immersion incidents. The effect of the victim’s age on these processes is also examined. A major protective role of hypothermia comes from a reduced meta- bolic rate and thus lowered oxygen con- sumption by body tissues. Although hypothermia may produce fatal cardiac arrhythmias such as ventricular fibrilla- tion, it is also associated with brady- cardia and peripheral vasoconstriction, both of which enhance oxygen supply to the heart and brain. The MDR also results in bradycardia and reduced peripheral blood flow, as well as laryngospasm, which protects victims against rapid in- halation of water. Studies of drowning and near-drowning accidents involving children and adults suggest that victim survival depends on the presence of both hypothermia and the MDR, as neither alone can provide adequate cerebral protection during long periods of hypoxia. Future lines of research are suggested and re- Introduce lated to improved patient care. topic; give paper’s aims INTRODUCTION and scope.
    [Show full text]