It is known that estrogen plays a role in the regulation of nor- mal reproductive tract function mediated, principally, by nuclear ERs (ER and ER ) [99]. Principal estrogenic effects in the uterus are mediated by ER , which is the predominant ER found in uterine tissue, regulating epithelial morphogenesis and uterine development [100–102]. In addition, uterine luminal epithelium (LE) height is a classic marker of high estrogen levels [103]. A pre- vious study showed that a treatment of herbicide pendimethalin (600 mg/kg/day) led an increase in rat uterine weight and mRNA ER expression, although the uterine mRNA ER and progesterone receptor expressions were not affected [104]. Additionally, expo- sure to bisphenol-A (BPA, 100 g/day) did not alter ER expression in the uterus and pituitary gland; however, it increased ER expres- sion in the hypothalamus of PND1-5 rats [105]. Here, the LNI rats had an increase in ER protein expression and a thickening of LE in the uteri. Schönfelder et al. [101] reported an increase