Phan Thieu X, Sahibzada Niaz, Freichel Marc, Miyares Rosa L, Ahern Gerard P
Department of Pharmacology and Physiology, Georgetown University, Washington DC 20007.
Department of Biology, Vinh University, Vinh City 43105, Vietnam.
Proc Natl Acad Sci U S A. 2025 May 27;122(21):e2503186122. doi: 10.1073/pnas.2503186122. Epub 2025 May 20.
In response to changing blood pressure, arteries adjust their caliber to control blood flow. This vital autoregulatory property, termed vascular myogenic tone, stabilizes downstream capillary pressure. Here, we reveal that tissue temperature, combined with intraluminal pressure, critically determines myogenic tone. Heating steeply activates tone in skeletal muscle, gut, brain, and skin arteries with temperature coefficients () of ~11 to 20. Each of these tissues has a distinct resting temperature, and we find that arterial thermosensitivity is tuned to this temperature, making myogenic tone sensitive to small thermal fluctuations. Interestingly, temperature and intraluminal pressure are sensed largely independently and the signals integrated to trigger myogenic tone. We demonstrate that thermosensitive channels TRPV1 and TRPM4 mediate heat-induced tone in skeletal muscle arteries with discrete temperature sensitivities. Similarly, TRPM4 contributes to heat-induced tone in gut and brain arteries. The half-maximal responses occur at approximately 31 °C for TRPV1 and 33 °C for TRPM4. Variations in tissue temperature are known to alter blood fluidity and therefore vascular conductance; remarkably, thermosensitive tone counterbalances this effect, thus protecting capillary integrity and fluid balance. In conclusion, thermosensitive myogenic tone is a fundamental homeostatic mechanism regulating tissue perfusion.
为响应血压变化,动脉会调整其管径以控制血流。这种至关重要的自动调节特性,即血管肌源性张力,可稳定下游毛细血管压力。在此,我们揭示组织温度与管腔内压力共同严格决定肌源性张力。加热会使骨骼肌、肠道、大脑和皮肤动脉中的张力急剧激活,温度系数()约为11至20。这些组织各自具有独特的静息温度,我们发现动脉热敏感性与该温度相匹配,使得肌源性张力对微小的温度波动敏感。有趣的是,温度和管腔内压力在很大程度上是独立感知的,且信号整合后触发肌源性张力。我们证明热敏通道TRPV1和TRPM4介导骨骼肌动脉中热诱导的张力,具有离散的温度敏感性。同样,TRPM4也参与肠道和大脑动脉中热诱导的张力。TRPV1的半数最大反应发生在约31℃,TRPM4的半数最大反应发生在约33℃。已知组织温度的变化会改变血液流动性,进而改变血管传导性;值得注意的是,热敏性张力可抵消这种影响,从而保护毛细血管完整性和液体平衡。总之,热敏性肌源性张力是调节组织灌注的一种基本稳态机制。