Daytime Unresponsiveness of the Human and Syrian Hamster Pineal to Adrenergic Stimulation

Abstract

The human melatonin rhythm is remarkably stable in the face of many other endocrine and metabolic disturbances. Daytime induction of sympathetic activity and injection of Beta-agonists do not stimulate levels of circulating or excreted melatonin in humans. This seems paradoxical in that the human nocturnal surge in blood and urinary melatonin does depend on sympathetic innervation to the pineal. The gland is sensitive to Beta-adrenergic stimulation at night; Beta-blocking drugs can eliminate the nocturnal melatonin surge in humans. The Syrian hamster has been developed as a model for the human findings. Its nocturnal melatonin surge is blocked by Beta-blockade or by pineal denervation. Injection of norepinephrine (NE) or isoproterenol (ISO) during the second half of the dark phase (after interruption of the endogenous melatonin surge by short light exposure) raises pineal melatonin content; injection outside this sensitive period does not. (js)

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1989
Accession Number
ADA228678

Entities

People

  • George M. Vaughan

Organizations

  • United States Army Institute of Surgical Research

Tags

DTIC Thesaurus Topics

  • Animals
  • Brain
  • Catecholamines
  • Central Nervous System
  • Chemistry
  • Diseases And Disorders
  • Endocrine Glands
  • Glands
  • Laboratory Animals
  • Melatonin
  • Menstrual Cycle
  • Nerves
  • Nervous System
  • Norepinephrine
  • Peripheral Nervous System
  • Sympathetic Nervous System
  • Vascular Diseases

Fields of Study

  • Biology
  • Medicine

Readers

  • Cardiovascular Physiology
  • Circadian Sleep-Wake Regulation and Chronobiology