Abstract
The conversion of testosterone to estradiol by cytochrome P450 aromatase (P450AROM) in the medial preoptic area is required for full expression of male sexual behavior in rats. Preoptic P450AROM activity is stimulated by androgens through an androgen-receptor mediated mechanism that regulates P450AROM gene expression. The mechanism of enzyme induction appears to be sexually dimorphic in several species leading to greater testosterone-stimulated P450AROM activity in males than in females. The present study was designed to determine whether the sex difference in androgen-regulated P450AROM activity is manifested at the levels of mRNA expression. We compared the concentrations of P450AROM mRNA and enzyme activity between five different treatment groups: intact males, castrated males (CX), ovariectomized females (OVX), CX males treated with dihydrotestosterone (CX+DHT), and OVX females treated with DHT (OVX+DHT). We found that unstimulated levels of P450AROM mRNA and enzyme activity in both the preoptic area and medial basal hypothalamus were similar in the CX and OVX groups. However, when treated with equivalent doses of DHT, the levels of P450AROM mRNA and enzyme activity in both brain regions were significantly higher in males than in females (i.e., CX+DHT group >OVX+DHT group). These results demonstrate that sex differences in the regulation of P450AROM in brain are exerted pretranslationally by androgen and suggest that gender differences in androgen responsiveness play an important role in regulating gene expression in the adult rat brain.
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Abdelgadir, S. E., Resko, J. A., Ojeda, S. R., Lephart, E. D., McPhaul, M. J., and Roselli, C. E. (1994).Endocrinology 135, 395–401.
Balthazart, J., Foidart, A., and Hendrick, J. C. (1990).Physiol. Behav. 47, 83–94.
Beyer, C., Green, S. J., and Hutchison, J. B. (1994).Endocrinology 135, 1220–1226.
Black, V. H. (1994).Endocrinology 135, 299–306.
Bonsall, R. W., Clancy, A. N., and Michael, R. P. (1992).Horm. Behav. 26, 240–254.
Bureau, M., Laschet, J., Bureau-Heeren, M., Hennuy, B., Minet, A., Wins, P., and Grisar, T. (1995).J. Neurochem. 65, 2006–2015.
Callard, G. V. (1981).Brain. Res. 204, 461–464.
Canick, J. A., Tobet, S. A., Baum, M. J., Vaccaro, D. E., Ryan, K. J., Leeman, S. E., and Fox, T. O. (1987).Steroids 50, 509–521.
Chirgwin, J. M., Przybyla, A. E., MacDonald, R. J., and Rutter, W. J. (1979).Biochemistry 18, 5294–5298.
Christensen, L. W. and Clemens, L. G. (1975).Endocrinology 97, 1545–1551.
Clancy, A. N., Zumpe, D., and Michael, R. P. (1995).Neuroendocrinology 61, 98–111.
Danielson, P. E., Forss-Petter, S., Brow, M. A., Calavetta, L., Douglass, J., Milner, R. J., and Sutcliffe, J. G. (1988).DNA 7, 261–267.
De Vries, G. J. (1990).J. Neuroendocrinol. 2, 1–13.
Fitzpatrick, S. L. and Richards, J. S. (1993).Mol. Endocrinology 7, 341–354.
Foidart, A., De Clerck, A., Harada, N., and Balthazart, J. (1994).Physiol. and Behav. 55, 453–464.
Gerall, A. A. and Ward, I. L. (1966).J. Comp. Physiol. Psychol. 62, 370–375.
Gilman, M. (1990). In:Current Protocols in Molecular Biology. Ausubel, F. M., Brent, R., Kingston, R. E., Moore, D. D., Seidman, J. G., Smith, J. A., and Struhl, K. (eds). Green and Wiley-Interscience: New York. pp. 4.7.1–4.7.6.
Gorski, R. A. (1985).Can. J. Physiol. Pharmacol. 63, 577–594.
Handa, R. J., Reid, D. L., and Resko, J. A. (1986).Biol. Reprod. 34, 293–303.
Harada, N., Abe-Dohmae, S., Loeffen, R., Foidart, A., and Balthazart, J. (1993).Brain. Res. 622, 243–256.
Honda, S., Harada, N., and Takagi, Y. (1994).Biochem. Biophys. Res. Comm. 198, 1153–1160.
Hutchison, J. B. (1990).Comp. Phys. 9, 27–44.
Ikeda, Y., Luo, X., Abbud, R., Nilson, J. H., and Parker, K. L. (1995).Mol. Endocrinology,9, 478–486.
Jakab, R. L., Horvath, T. L., Leranth, C., Haracla, N., and Naftolin, F. (1993).J. Steroid Biochem. Molec. Biol. 44, 481–498.
Krey, L. C., MacLusky, N. J., Davis, P. G., Lieberburg, I., and Roy, E. J. (1982).Endocrinology 110, 2159–2167.
Lephart, E. D., Peterson, K. G., Noble, J. F., George, F. W., and McPhaul, M. J. (1990).Mol. Cell. Endocrinol. 70, 31–40.
Lephart, E. D., Simpson, E. R., and Ojeda, S. R. (1992).J. Neuroendocrinol. 4, 29–35.
Lephart, E. D. and Ojeda, S. R. (1990).Neuroendocrinology 51, 385–393.
Lowry, O. H., Rosebrough, N. J., Farr, A. L., and Randall, R. J. (1951).J. Biol. Chem. 193, 265–267.
Naftolin, F., Ryan, K. J., Davies, I. J., Reddy, V. V., Flores, F., Petro, Z., Kuhn, M., White, R. J., Takaoka, Y., and Wolin, L. (1974).Rec. Prog. Horm. Res. 31, 295–319.
Noma, K., Sato, B., Yano, S., and Yamamura, Y. (1975).J. Steroid. Biochem. 6, 1261–1265.
Resko, J. A., Malley, A., Begley, D., and Hess, D. L. (1973).Endocrinology 93, 156–161.
Rissman, E. F., Harada, N., and Roselli, C. E. (1996).J. Neuroendocrinology 8, 199–210.
Roselli, C. E., Horton, L. E., and Resko, J. A. (1987).Biol. Reprod. 37, 628–633.
Roselli, C. E. (1991a).Endocrinology 128, 1310–1316.
Roselli, C. E. (1991b).Neuroendocrinology 53, 79–84.
Roselli, C. E. and Resko, J. A. (1984).Endocrinology 114, 2183–2189.
Roselli, C. E. and Resko, J. A. (1991). In:Neuroendocrine Research Methods. Greenstein, B. (ed.). Harwood Academic Publishers: Reading, UK, pp. 937–951.
Roselli, C. E. and Resko, J. A. (1993).J. Steroid. Biochem. Molec. Biol. 44, 499–508.
Roy, M. M. and Goy, R. W. (1988).Horm. Behav. 22, 315–323.
Sachs, B. D., Pollak, E. I., Krieger, M. S. and Barfield, R. J. (1973).Science 181, 770–771.
Sachs, B. D. and Meisel, R. L. (1994). In:The Physiology of Reproduction. Knobil, E. and Neil, J. (eds.). Raven: New York, pp. 3–105.
Schumacher, M. and Balthazart, J. (1986).Brain. Res. 370, 285–293.
Steimer, T. and Hutchison, J. B. (1990).J. Neurobiol. 21, 787–795.
Steimer, T. H. and Hutchison, J. B. (1989).Brain. Res. 480, 335–339.
Van Doorn, E. J., Burns, B., Wood, D., Bird, C. E., and Clark, A. F. (1975).J. Steroid. Biochem. 6, 1549–1554.
Ward, I. L. (1969).Horm. Behav. 1, 25–36.
Yamada, K., Harada, N., Tamaru, M., and Takagi, Y. (1993).Biochem. Biophys. Research Comm. 195, 462–468.
Yuan, H., Bowlby, D. A., Brown, T. J., Hochberg, R. B., and MacLusky, N. J. (1995).Endocrinology 136, 96–105.
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Roselli, C.E., Abdelgadir, S.E., Jorgensen, E. et al. Sex differences in androgen-regulated cytochrome P450 aromatase mRNA in the rat brain. Endocr 5, 59–65 (1996). https://doi.org/10.1007/BF02738657
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DOI: https://doi.org/10.1007/BF02738657