Summary
In two conscious dogs in standardized environments, the temperatures of spinal cord or hypothalamus were altered independently of each other and the resulting changes in heat production (shivering) and in respiratory evaporative heat loss (panting) were measured and correlated with these changes in temperatures.
Spinal cord cooling at 18 and 24°C air temperature increased heat production by about −0.7 Kcal/(kg·h·°C). The mean spinal cord temperature at which this occurred was between 37.30 and 37.80°C. Under the same conditions hypothalamic cooling increased heat production by about −0.7 Kcal/(kg·h·°C). The temperature at which this occurred was between 38.40 and 38.75°C.
Spinal cord heating at 18, 24, and 30°C air temperature increased the respiratory evaporative heat loss by +0.9 to 1.2 Kcal/(kg·h·°C) above a mean spinal cord temperature between 40.00 and 41.50°C. Hypothalamic heating at 30°C air temperature increased the respiratory evaporative heat loss by +0.9 Kcal/(kg·h·°C). For all environments the hypothalamic threshold temperature lay between 38.75 and 42.40°C.
The results suggest that in the dog, spinal cord and hypothalamus represent basically equivalent core sensors of temperature.
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Jessen, C., Mayer, E.T. Spinal cord and hypothalamus as core sensors of temperature in the conscious dog. Pflugers Arch. 324, 189–204 (1971). https://doi.org/10.1007/BF00586418
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DOI: https://doi.org/10.1007/BF00586418