Androgen receptor levels in cranial nerve nuclei and tongue muscles in rats.

Specific in vitro binding of 3H-methyltrienolone (R1881) was demonstrated in 100,000 X g supernatant (cytosol) of hypoglossal, facial, and cochlear nuclei and tongue muscles of adult rats. Binding sites in these cranial nerve nuclei and tongue muscles were of high affinity, limited capacity, with steroid specificity; and they were capable of translocation to the cell nuclei in vivo. Accordingly, an androgen receptor system with properties very much akin to the androgen receptors described in the forebrain limbic regions has been quantitatively demonstrated for the first time in brain stem nuclei. Because of its widespread presence in neurons of the brain stem and spinal cord, androgen receptors may have important roles in regulation of neuron physiology beyond the sphere of reproductive function, including mediating androgen effects on regeneration of the hypoglossal nerve reported previously.