Spinal cord and hypothalamus as core sensors of temperature in the conscious dog
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In two conscious dogs at standardized external conditions, the temperatures of the spinal cord and hypothalamus were altered simultaneously and were correlated with heat production (shivering) and respiratory evaporative heat loss (panting).
Combined cooling of spinal cord and hypothalamus at 18, 24, and 30°C air temperature increased heat production by up to 10.2 Kcal/(kg·h). Combined heating of the spinal cord and hypothalamus at the same environmental conditions increased respiratory evaporative heat loss by up to 4.5 Kcal/(kg·h).
Compared with the effects of cooling either the spinal cord or the hypothalamus, cooling both together increased the slope of the regression and elevated the threshold temperatures for shivering. With regard to respiratory evaporative heat loss, heating the spinal cord and hypothalamus together mainly lowered the threshold temperatures as compared with warming each area independently.
The results suggest that temperature signals, simultaneously generated in spinal cord and hypothalamus, are added to give a combined drive to the effector systems.
Key-WordsTemperature Regulation Hypothalamic Temperature Spinal Cord Temperature Core Sensors of Temperature
SchlüsselwörterTemperaturregulation Hypothalamustemperatur Rückenmarkstemperatur Kerntemperaturfühler
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