Thermotolerance preserves endothelial vasomotor function during ischemia/reperfusion

Area of Science:

• Physiology
• Vascular Biology
• Medical Research

Background:

• Ischemia/reperfusion (I/R) injury impairs endothelial function, leading to reduced vasodilatation and microvascular
• no reflow.
• Thermotolerance (T) is known to mitigate I/R-induced microvascular damage.

Purpose of the Study:

• To investigate the protective effects of thermotolerance on I/R-induced vasomotor dysfunction and the
• no reflow
• phenomenon in mesenteric arterioles.

Main Methods:

• Sprague-Dawley rats were divided into I/R and thermotolerance + I/R (T + I/R) groups.
• I/R injury was induced via vascular pedicle occlusion, followed by reperfusion.
• Vasomotor function and
• no reflow
• were assessed using intravital microscopy, measuring responses to acetylcholine and sodium nitroprusside.

Main Results:

• I/R significantly decreased endothelium-dependent vasodilatation and caused
• no reflow
• in 16/28 rats.
• Thermotolerance (T + I/R) attenuated the impairment of endothelium-dependent dilatation (P<0.01) and reduced
• no reflow
• to 4/16 rats (P<0.05).
• Endothelium-independent dilatation remained unaffected by I/R.

Conclusions:

• Thermotolerance effectively preserves endothelial vasomotor function following ischemia/reperfusion injury.
• Heat preconditioning significantly reduces the incidence of microvascular
• no reflow
• after I/R.
• Thermotolerance represents a promising strategy for mitigating I/R-induced vascular complications.