Ultrastructural effects of tamoxifen on uterus in rats.

: Tamoxifen is a triphenylethylene derivative commonly used in the treatment of breast cancer The Wistar rats (9 weeks old, 180-200 g body weight) used in these trials were divided into two groups of 20 animals each (control and experimental group). Animals of the experimental group were given drinking water containing 200 μg/kg tamoxifen citrate for a period of 30 day. At the end of exposure, body and uterus weights were measured. There was no statistical difference in the uterus weights between the control and treated groups (p < 0,05). Squamous metaplasia, characterized by the presence of stratified squamous epithelium on the lumenal surface of the uterus and the lining of the luminal surface of uterine glands was seen in some animals that had received tamoxifen. Ultrastructural changes were revealed in the form of vacularization of cell cytoplasm and The cytoplasm contained areas of low electron density. Not only was the cytoplasm full with intense crystalized and degeneration in mitochondria.