Histological Changes in Reproductive Organs of Pubescent Male Mice in Response to ICI 182, 780 Treatment and Recovery of the Organs with Time

Abstract

ICI 182, 780 (ICI) has been used as an estrogen receptor inhibitor in several mammalian species. This study was conducted to observe histological changes in the reproductive system of pubescent male mice following ICI treatment, as well as to investigate the recovery of the organs over time. To accomplish this, ICI at 5 mg/0.1 ml of castor oil was subcutaneously injected into 5-week-old male mice once per week for 4 weeks. The mice were then randomly divided into no-recovery, 150-day recovery, and 300-day recovery groups. The testis of the no-recovery group showed atrophy of the seminiferous tubules, with decreased Sertoli cell numbers and thickness of the germinal epithelium. In the epididymis, the cell height of epithelial tissues was altered, but these changes were not observed in the 300-day recovery group. In the efferent ductule, the luminal diameter was increased, but the cell height of the epithelial tissues was decreased. In the prostate and seminal vesicles, the cell height of the epithelial tissues was increased, and these changes were not observed in the 150-day recovery group. These results show that ICI causes histological changes in pubescent male reproductive organs but that these changes are resolved with time.