Pflügers Archiv

, Volume 335, Issue 4, pp 323–334 | Cite as

Temperature-sensitive neurons in the brain stem: Their responses to brain temperature at different ambient temperatures

  • R. F. Hellon


Unit recordings have been made in the hypothalamus of cats and rabbits under urethane anaesthesia. The final position of each electrode penetration was marked by the ejection of a dye. Techniques used enabled brain temperature and ambient temperature to be controlled.

Neurons were found whose mean firing rate was positively or negatively correlated with changes of brain temperature over a range of 4°C. Some of these neurons also responded when ambient temperature over a range of 4°C. Some of these neurons also responded when ambient temperature was raised to 40°C or lowered to 10°C. In four cases, lowering, but not raising, ambient temperature was found to modify the neuron's responses to brain temperature changes. Two forms of modulation were found. In one, the curve relating brain temperature and firing rate was shifted without showing a change in slope (sensitivity). In the other, the slope of curve changed, so that the sensitivity of the neuron to brain temperature was altered. Both types of modulation are consistent with current models of temperature regulation involving receptors in the hypothalamus and in the skin.

Key words

Temperature Neurons Hypothalamus Ambient Temperature 


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Copyright information

© Springer-Verlag 1972

Authors and Affiliations

  • R. F. Hellon
    • 1
  1. 1.National Institute for Medical ResearchLondonEngland

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