Clomiphene citrate potentiates the adverse effects of estrogen on rat testis and down- regulates the expression of steroidogenic enzyme genes  Shilpa Bharti, M.Sc., M.M. Misro, Ph.D., Umesh Rai, Ph.D.  Fertility and Sterility  Volume 99, Issue 1, Pages 140-148.e5 (January 2013) DOI: 10.1016/j.fertnstert.2012.08.050 Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

Figure 1 Histologic sections of rat testes stained with hematoxylin and eosin after 30 days of drug treatment. (A) Vehicle control shows normal spermatogenesis. (C) Clomiphene citrate (CC) treatment induces partial arrest of spermatogenesis, and it is completely arrested with either (B) estradiol-3-benzoate (EB) or (D) CC+EB treatment (n = 6 per group; ×400). Germ cell numbers per tubule (mean ± SD) from 20 randomly selected seminiferous tubules were quantified from each testis section of control versus treated rats for (E) 15 and (F) 30 days. A significant decrease in number of germ cells is observed in rats treated with either EB or CC+EB for 30 days. *P<.01; **P<.01; ***P<.001; compared with vehicle-treated control. #P<.05; ##P<.01; compared with CC alone. $P<.05; compared with EB alone. Fertility and Sterility 2013 99, 140-148.e5DOI: (10.1016/j.fertnstert.2012.08.050) Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

Figure 2 A representative rat testis section showing TUNEL-positive cells/tubule from 10 randomly selected seminiferous tubules. (A) Vehicle-treated control, (B) EB-alone treatment, (C) CC-alone treatment, and (D) CC+EB treatment for 30 days (×400). Note the rise in TUNEL-positive cells (arrows) in testis sections of treated rats, after (E) 15 and (F) 30 days. *P<.001; compared with vehicle-treated control (n = 6 per group). #P<.05; compared with CC alone. $P<.05; compared with EB alone. Abbreviations as in Figure 1. Fertility and Sterility 2013 99, 140-148.e5DOI: (10.1016/j.fertnstert.2012.08.050) Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

Figure 3 LH, T, and E2 (serum, intratesticular, IT) in rats (n = 6 per group) treated with EB, CC, or CC+EB for 15 and 30 days. Significant decline in serum (A) LH and (B) testosterone and (D) IT testosterone coincided with (C) serum and (E) IT E2 rise after 30 days of treatment. *P<.01; **P<.01; ***P<.001; compared with vehicle-treated control group. #P<.05; ##P<.01; compared with CC alone. $P<.05; compared with EB alone. Abbreviations as in Figure 1. Fertility and Sterility 2013 99, 140-148.e5DOI: (10.1016/j.fertnstert.2012.08.050) Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions

Figure 4 Expression analysis of steroidogenic enzyme genes. Down-regulation of transcript levels of (A) StAR, (B) p450scc, (C) 3β-HSD, and (D) p450c17 was seen with EB or CC+EB treatment. CC-alone treatment induced identical attenuation only after 30 days of treatment. (E) 17βHSD and (F) 5α-reductase transcripts remained unchanged. (J) Corresponding protein expression in Western blots (n = 3) followed an identical trend. (K) Aromatase expression in (H) liver and (I) brain declined further with CC+EB treatment, which effectively countered the EB-induced rise in (G) testis. *P<.01; **P<.001; ***P<.001; compared with vehicle-treated control. #P<.05; ##P<.01; ###P<.001; compared with CC alone. $P<.05; compared with EB alone. Abbreviations as in Figure 1. Fertility and Sterility 2013 99, 140-148.e5DOI: (10.1016/j.fertnstert.2012.08.050) Copyright © 2013 American Society for Reproductive Medicine Terms and Conditions