This study aimed to evaluate the physical exercise-induced neuronal activation in brain nuclei controlling thermoregulatory responses in hypertensive and normotensive rats. Sixteen-week-old male normotensive Wistar rats (NWRs) and spontaneously hypertensive rats (SHRs) were implanted with an abdominal temperature sensor. After recovery, the animals were subjected to a constant-speed treadmill running (at 60% of the maximum aerobic speed) for 30 min at 25 °C. Core (T_core) and tail-skin (T_skin) temperatures were measured every minute during exercise. Ninety minutes after the exercise, the rats were euthanized, and their brains were collected to determine the c-Fos protein expression in the following areas that modulate thermoregulatory responses: medial preoptic area (mPOA), paraventricular hypothalamic nucleus (PVN), and supraoptic nucleus (SON). During treadmill running, the SHR group exhibited a greater increase in T_core and an augmented threshold for cutaneous heat loss relative to the NWR group. In addition, the SHRs showed reduced neuronal activation in the mPOA (< 49.7%) and PVN (< 44.2%), but not in the SON. The lower exercise-induced activation in the mPOA and PVN in hypertensive rats was strongly related to the delayed onset of cutaneous heat loss. We conclude that the enhanced exercise-induced hyperthermia in hypertensive rats can be partially explained by a delayed cutaneous heat loss, which is, in turn, associated with reduced activation of brain areas modulating thermoregulatory responses.

本研究旨在评估体育锻炼诱导的脑核神经元激活，控制高血压和正常血压大鼠的体温调节反应。16 周大的雄性血压正常 Wistar 大鼠 (NWRs) 和自发性高血压大鼠 (SHRs) 被植入腹部温度传感器。恢复后，动物在 25°C 下进行恒速跑步机跑步（以最大有氧速度的 60%）30 分钟。核心（T_核）和尾皮（T_皮）) 运动期间每分钟测量一次体温。运动后 90 分钟，对大鼠进行安乐死，并收集它们的大脑以确定以下调节体温调节反应区域的 c-Fos 蛋白表达：内侧视前区 (mPOA)、室旁下丘脑核 (PVN) 和视上核（儿子）。在跑步机跑步过程中，SHR组表现出更大的T_核增加和相对于 NWR 组的皮肤热损失增加的阈值。此外，SHR 在 mPOA (< 49.7%) 和 PVN (< 44.2%) 中显示出神经元激活减少，但在 SON 中没有。高血压大鼠 mPOA 和 PVN 中较低的运动诱导激活与皮肤热量损失的延迟发生密切相关。我们得出结论，高血压大鼠运动诱发的体温过高可以部分解释为延迟的皮肤散热，这反过来又与调节体温调节反应的大脑区域的激活减少有关。