Expression pattern of phospholipid hydroperoxide glutathione peroxidase messenger ribonucleic acid in mouse testis

To determine the expression pattern of phospholipid hydroperoxide glutathione peroxidase (PHGPx) mRNA in testes, Northern (3-, 8-, 40-, and 80-wk-old mice) and in situ (8-wk-old mice) hybridization analyses using digoxigenin-labeled RNA probes for PHGPx were performed in the testes of ICR mice. PHGPx mRNA in the mouse testes was first expressed at 3 wk of age, greatly increased at 8 wk, and persisted at the high level until 80 wk. According to in situ analysis, the PHGPx mRNA was expressed stage-specifically during spermatogenesis. It first appeared in pachytene spermatocytes of stage X, gradually increased in round spermatids during early spermiogenesis, and reached a peak in step 10-11 elongating spermatids. After step 12, PHGPx mRNA began to show a progressive decline in the spermatids and was weakly detected in step 16 spermatids. However, the signal was not detected in spermatogonia or early spermatocytes. On the other hand, according to in situ and reverse transcription-polymerase chain reaction analyses, PHGPx mRNA was also expressed in Leydig cells. These findings suggest that PHGPx in testes may be closely involved in spermatogenesis as well as having a general antioxidant function.