SEX DIFFERENCES IN RESPONSE TO EXPERIMENTALLY INDUCED PAIN

Area of Science:

• Neuroscience
• Physiology
• Pain Research

Background:

• The Transient Receptor Potential Vanilloid 1 (TRPV1) is crucial for sensing heat and pain.
• Hormonal fluctuations during the ovulatory menstrual cycle (OMC) may influence pain perception and TRPV1 expression.

Purpose of the Study:

• To investigate the relationship between thermal/mechanical sensations, pain thresholds, and TRPV1 levels in young males and females.
• To examine gender and ovulatory menstrual cycle phase differences in pain perception and TRPV1 dynamics.

Main Methods:

• Assessed thermal and mechanical pain thresholds and tolerance in healthy young males and females.
• Measured Transient Receptor Potential Vanilloid 1 (TRPV1) receptor protein levels.
• Compared data between sexes and across the follicular and luteal phases of the ovulatory menstrual cycle (OMC).

Main Results:

• Males demonstrated significantly higher mechanical pain tolerance and heat pain thresholds than females in both OMC phases.
• Mechanical pain, mechanical pressure, cold pain, and heat sensation thresholds were higher in males, particularly during the luteal phase.
• TRPV1 levels showed significant gender and interphase differences, peaking in females during the luteal phase and lowest in females during the follicular phase.

Conclusions:

• Significant gender-based differences exist in pain perception, modulated by ovulatory menstrual cycle phases in females.
• TRPV1 levels are dynamically regulated by gender and ovulatory menstrual cycle phase, suggesting a role in sex-specific pain sensitivity.