Brain Angiotensin and Body Fluid Homeostasis

Access this Article

Author(s)

    • MAY C.
    • Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne
    • MCALLEN R. M.
    • Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne
    • OLDFIELD B. J.
    • Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne
    • WEISINGER R. S.
    • Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne

Abstract

Angiotensinogen, the precursor molecule of the peptides angiotensin I, II, and III, is synthesized in the brain and the liver. Evidence is reviewed that angiotensin II, and possibly angiotensin III, that are generated within the brain act within neural circuits of the central nervous system to regulate body fluid balance. Immunohistochemical studies in the rat brain have provided evidence of angiotensin-containing neurons, especially in the hypothalamic paraventricular nucleus, subfornical organ, periventricular region, and nucleus of the solitary tract, as well as in extensive angiotensin-containing fiber pathways. Angiotensin immunoreactivity is observed by electron microscope in synaptic vesicles in several brain regions, the most prominent of these being the central nucleus of the amygdala. Neurons in many parts of the brain (lamina terminalis, paraventricular and parabrachial nuclei, ventrolateral medulla, and nucleus of the solitary tract) known to be involved in the regulation of body fluid homeostasis exhibit angiotensin receptors of the AT<sub>1</sub> subtype. Pharmacological studies in several species show that intracerebroventricular administration of AT<sub>1</sub> receptor antagonist drugs inhibit homeostatic responses to the central administration of hypertonic saline, intravenous infusion of the hormone relaxin, or thermal dehydration. Responses affected by centrally administered AT<sub>1</sub> antagonists are water drinking, vasopressin secretion, natriuresis, increased arterial pressure, reduced renal renin release, salt hunger, and thermoregulatory adjustments. We conclude that angiotensinergic neural pathways in the brain probably have an important homeostatic function, especially in regard to osmoregulation and thermoregulation, and the maintenance of arterial pressure.<br>

Journal

  • The Japanese Journal of Physiology

    The Japanese Journal of Physiology 51(3), 281-289, 2001-06

    THE PHYSIOLOGICAL SOCIETY OF JAPAN

References:  85

Codes

  • NII Article ID (NAID)
    10008293516
  • NII NACSIS-CAT ID (NCID)
    AA00691224
  • Text Lang
    ENG
  • Article Type
    REV
  • ISSN
    0021521X
  • NDL Article ID
    5840170
  • NDL Source Classification
    ZS8(科学技術--医学--解剖学・生理学・生化学)
  • NDL Call No.
    Z53-D40
  • Data Source
    CJP  NDL  J-STAGE 
Page Top