EXPRESSION OF ANDROGEN RECEPTOR PROTEIN WITHIN THE LUMBAR SPINAL-CORDDURING ONTOLOGIC DEVELOPMENT AND FOLLOWING ANTIANDROGEN INDUCED CRYPTORCHIDISM

One of the leading hypotheses regarding androgenic regulation of testi cular descent is that the lumbar genitofemoral nucleus is morphologica lly altered by testosterone during a specific prenatal period. This hy pothesis is based on the unproved assumption that androgen receptor is present in the fetal spinal cord. Using immunohistochemistry we ident ified androgen receptor in the rat lumbar spinal cord on gestational d ay 15, a day before the onset of maximal androgenic action for testicu lar descent. Experiments were performed to determine whether alteratio ns in the morphology of the genitofemoral nucleus are associated with flutamide induced cryptorchidism. Studies revealed a reduction of moto neuron number in rats with flutamide induced cryptorchidism (124.2 +/- 18.9) compared to rats exposed to flutamide without cryptorchidism (2 69.3 +/- 20.2) and/or male controls (291.0 +/- 14.5, p < 0.01). These findings support the hypothesis that androgens can directly regulate d evelopment and morphology of the genitofemoral nucleus.