[Androgen receptors in muscles mediate the trophic effect of testosterone on axotomized neurons]

In order to further explore the hypothesis that muscles are the primary action site for testosterone, the present study examined the effect of androgen receptor blockade in effector muscles on the efficacy of testosterone in preventing neuronal cell loss following axotomy. Hydroxyflutamide (HF), an androgen antagonist that acts competitively at the hormone receptor site, was administered into muscles of the tongue when animals were treated with testosterone following unilateral transection of the hypoglossal and facial nerves. The ability of testosterone to prevent neuronal cell loss in the axotomized hypoglossal and facial motor nucleus was examined. The results demonstrated that hydroxyflutamide completely negates the survival-promoting effect of testosterone on axotomized motoneurons.