Hormonally mediated lordosis in female rats: Actions of flutamide and an aromatization inhibitor

Abstract

Agents which interfere with androgen metabolism or receptor binding diminished androgen-induced, but not estrogen-induced lordotic behavior in female rats. The non-steroidal antiandrogen, flutamide, reduced the amount of lordosis displayed by females receiving 250 μg testosterone propionate (TP) plus progesterone (P). Flutamide (10 mg) did not affect the lordotic behavior of animals receiving estradiol benzoate (0.5 μg or 0.25 μg EB) plus P. Similarly, the aromatization inhibitor 1,4,6-androstatriene-3,17-dione (ATD; 10 mg) blocked TP plus P induced lordosis but failed to alter EB (10 μg) plus P induced lordosis. These results suggest that androgen-induced lordosis occurs after the testosterone molecule becomes bound to a receptor and is enzymatically converted to estrogenic metabolites.