All-trans retinoic acid disrupts development in ex vivo cultured fetal rat testes. I: altered seminiferous cord maturation and testicular cell fate

Exposure to excess retinoic acid disrupts the development of the mammalian testicular seminiferous cord. However, the molecular events surrounding retinoic acid-driven loss of cord structure have not previously been examined. To investigate the mechanisms associated with this adverse developmental effect, fetal rat testes were isolated on gestational day 15, after testis determination and the initiation of cord development, and cultured in media containing all-trans retinoic acid (ATRA; 10-8 to 10-6 M) or vehicle for 3 days. ATRA exposure resulted in a concentration-dependent decrease in the number of seminiferous cords per testis section and number of germ cells, assessed by histopathology and immunohistochemistry. Following 1 day of culture, genome-wide expression profiling by microarray demonstrated that ATRA exposure altered biological processes related to retinoid metabolism and gonadal sex determination. Real-time RT-PCR analysis confirmed that ATRA enhanced the expression of the ...