Regulation of Gamma-Glutamyl INTRODUCTION

Gamma-glutamyl transpeptidase (GGT; EC 23.2.2) is an important enzyme involved in glutathione metabolism . Previous studies have shown that GGT is present in epididymal epithelial cells and luminal fluids . Even though the function of epididymal GGT is unclear, a recent transgenic study showed that a hypoplastic epididymal epithelium was present in GGTml/GGTml mice. It has been proposed that epididymal GGT may function to protect spermatozoa from oxidative stress in the epididymal duct and/or to recover extracellular cysteine for the synthesis of epididymal proteins.