Immunolocalization of estrogen receptor beta, androgen receptor and Ki-67 protein in testicular tissues of unilateral cryptorchidism boar

This study was performed to investigate histological structure, expressions of estrogen receptor beta (ERβ), androgen receptor (AR) and proliferation marker (Ki-67 protein) in scrotal and abdominal testicular tissues of unilateral cryptorchidism prepubertal boars. Testicular tissues were obtained from 8 unilateral cryptorchidism boars. Immunohistochemical staining for ERβ, AR and Ki-67 protein was performed by avidin-biotin-peroxidase complex (ABC) method. The similar histological structure of both scrotal and abdominal testicular tissues was observed. Immunolocalization of Ki-67 was found in the nuclei of germ cells, interstitial cells and Sertoli cells of both scrotal and abdominal testicular tissues. For ERβ and AR, the immunolocalization was found in germ cells and interstitial cells of both scrotal and abdominal testicular tissues. Based on the statistical analysis, the ERβ expression in the interstitial area of scrotal testis was significantly higher than in the abdominal testis. A tendency of more expressions of Ki-67 protein (p=0.40) in the seminiferous tubule of the scrotal testicular tissues than in the abdominal testicular tissues was found. The expressions of AR in scrotal and abdominal testicular tissues were not significantly different. In conclusion, the histological structures of scrotal and abdominal testis of unilateral cryptorchidism boars are not different. However, there are differences in their immunolocalization patterns between the scrotal and abdominal testis as well as seminiferous tubules and interstitial areas.