The testicular feminized rat: a naturally occurring model of androgen independent brain masculinization

Although genotypically male (XY), the testicular feminized rat develops as an anatomic female because of an inherited deficiency in intracellular androgen receptors that prevents androgen imprinting of sexual primordia. However, the ability of testicular feminized rats to exhibit male-like sexual behavior and little feminine sexual behavior suggests that the brain can be masculinized without androgens.