Effect of ambient temperature on arterial pressure variability during sleep in the rat

Abstract

Changes in mean arterial pressure (MAP) and heart rate (HR) during sleep were recorded at three ambient temperatures (T(a): 16, 22 and 28°C). MAP and HR during sleep increased with lowering of P(a). The increase in MAP during the transition from NREM to REM sleep was decreased by lowering the T(a). At 28°C, the average HR increased in going from NREM to REM sleep, while, at 16°C, it decreased. The coefficient of variation (CV%) of the MAP during REM sleep decreased as the T(a) was lowered, while that seen during NREM sleep was unchanged. This study suggests that T(a) has a greater effect than sleep stage on the MAP and HR, and that MAP variability during REM sleep is greater at higher T(A).