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Thermally induced salivary secretion in anesthetized rats

  • Teruo Nakayama
  • Kazuyuki Kanosue
  • Hideto Tanaka
  • Tatsurou Kaminaga
Heart, Circulation, Respiration and Blood; Environmental and Exercise Physiology

Abstract

Effect of thermal stimulation on salivary secretion was examined in urethane anesthetized (i.p., 1.0 g/kg) rats. First, rectal temperature (T re) was maintained at various levels by warming the whole trunk with a heating blanket. Copious salivary secretion occurred whenT re reached a threshold value above 40°C, which is considerably higher than the threshold for tail vasodilation. Local warming of the scrotum, face, or hypothalamus also elicited salivary secretion, but only ifT re was in a limited range just below the threshold temperature at whichT re alone would induce salivary secretion. The higher theT re within that limited range, the lower the temperature of the site locally warmed at which salivary secretion began. Changes in temperature of the abdomen, not including the scrotum, modulated the salivary secretion elicited by scrotal warming. Hypothalamic and scrotal temperatures interacted with each other to affect salivary secretion. Temperature signals from both core and periphery thus appear to be integrated in bringing about salivary secretion. Thermally induced salivary secretion may function as a basis for saliva spreading behavior observed in rats in a hot environment.

Key words

Salivary secretion Hyperthermia Scrotal temperature Abdominal temperature Facial temperature Hypothalamic temperature Rat 

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Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • Teruo Nakayama
    • 1
  • Kazuyuki Kanosue
    • 1
  • Hideto Tanaka
    • 1
  • Tatsurou Kaminaga
    • 1
  1. 1.Department of PhysiologyOsaka University Medical SchoolKita-ku, OsakaJapan

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