The role of transient receptor potential vanilloid receptor-1 (TRPV1) has been primarily investigated in pain sensory neurons. Relatively, little research has been performed in testicular cells. TRPV1 is abundantly expressed in Leydig cells of young adult mice. This study was conducted to determine the role of the TRPV1 channel in Leydig cells. TRPV1 modulators and testosterone were treated to the mouse Leydig cell line TM3 cells for 24 h. Capsaicin, a TRPV1 activator, dose-dependently induced cell death, whereas capsazepine, a TRPV1 inhibitor, inhibited capsaicin-induced cell death. Testosterone treatment reduced capsaicin-induced cell death. High concentrations of testosterone decreased TRPV1 mRNA and protein expression levels. However, TRPV1 modulators did not affect testosterone production. These results showed that capsaicin induced cell death of Leydig cells and that testosterone reduced capsaicininduced cell death. Our findings suggest that testosterone may regulate the survival of Leydig cells in young adult mice by decreasing the expression level of TRPV1.

ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
CONCLUSION
CONFLICTS OF INTEREST
ACKNOWLEDGEMENTS
AUTHOR CONTRIBUTIONS
AUTHOR’S POSITION AND ORCID NO
REFERENCES

• Eun-Jin Kim(Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea)
• Long Cao Dang(Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Department of Convergence Medical Science, Gyeongsang National University)
• Marie Merci Nyiramana(Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Department of Convergence Medical Science, Gyeongsang National University)
• Adrian S. Siregar(Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Department of Convergence Medical Science, Gyeongsang National University)
• Min-Seok Woo(Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea)
• Chang-Woon Kim(Department of Obstetrics and Gynecology, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea)
• Dawon Kang(Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Department of Convergence Medical Science, Gyeongsang National University) Corresponding author