TRPV4 plays an important role in rat prefrontal cortex changes induced by acute hypoxic exercise

Area of Science:

• Neuroscience
• Exercise Physiology
• Altitude Medicine

Background:

• Exercise capacity decline during altitude training is a significant concern for athletes.
• Central fatigue mechanisms under hypoxic conditions require further elucidation.
• The role of Transient Receptor Potential Vanilloid 4 (TRPV4) in exercise-induced fatigue is not fully understood.

Purpose of the Study:

• To investigate the effects of TRPV4 on central fatigue induced by acute hypoxic exercise.
• To explore the mechanism of exercise capacity decline in athletes during early-stage altitude training.

Main Methods:

• 120 male Wistar rats were exposed to normoxia, simulated 2500m, and 4500m altitudes.
• Rats underwent incremental load exercise, with tissues collected at different exertion levels (quiet, 5-level, 8-level, exhausted).
• Measurements included intracellular calcium ion concentration and expression of TRPV4 using HE staining, ELISA, immunohistochemistry, RT-qPCR, and fluorescence staining.

Main Results:

• Hypoxic exercise led to increased venous congestion and edema compared to normoxia.
• 5,6-EET levels and TRPV4 expression in the prefrontal cortex significantly increased with exercise load and hypoxia.
• Calcium ion concentration was elevated during exercise, particularly at higher altitudes, and TRPV4 expression correlated with this increase.

Conclusions:

• Acute hypoxic exercise upregulates TRPV4 channel expression in the prefrontal cortex.
• Lower ambient oxygen concentrations exacerbate TRPV4 channel expression.
• TRPV4 channel may play a crucial role in calcium overload contributing to central fatigue during acute hypoxic exercise.