Objective: To quantify the amount of AR messenger RNA (mRNA) and to analyze the presence and functionality of the AR protein in X- and Y-carrier human spermatozoa.
Design: A molecular and cellular research study.
Setting: Academic research clinic and laboratories.
Patient(s): Ten normozoospermic volunteers.
Intervention(s): Sperm were analyzed for expression of AR mRNA and protein. The functionality of AR protein was assessed after incubation with 1 nM of synthetic androgen.
Main outcome measure(s): Reverse-transcription polymerase chain reaction (PCR), real-time PCR, Western immunoblotting, confocal immunofluorescence, and fluorescence in situ hybridization analysis were performed.
Result(s): A significant amount of AR mRNA (around 30% of that found in the testis) was found in sperm. Androgen receptor protein was found in both X- and Y-carrier spermatozoa and translocates into the nucleus in the presence of synthetic androgen.
Conclusion(s): A functional AR is expressed in human sperm. In view of the fact that AR protein is found in both X- and Y-carrier spermatozoa, it most probably is translated in earlier steps of spermatogenesis and moves to Y-carrier spermatids through the cytoplasmic bridges.