Nuclear uptake of testosterone in the dove preoptic area.
After intramuscular injection of tritiated testosterone, the tracer and its active metabolites, 5 alpha-dihydrotestosterone and estradiol-17 beta were taken up in vivo by preoptic cell nuclei in the male dove brain. An inactive metabolite, 5 beta-androstane-3 alpha-17 beta-diol, occurred only in the non-nuclear compartment. Saturable nuclear uptake of testosterone was higher in the preoptic area than in adjacent nontarget areas. The results suggest that the metabolic pathways demonstrated previously in vitro are all active in vivo, and only testosterone and its active metabolites interact with the cell nucleus.
D000818:Animals; D001717:Birds; D002467:Cell Nucleus / Q000378:metabolism; D013196:Dihydrotestosterone / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism; D008297:Male; D011301:Preoptic Area / Q000378:metabolism*; D013739:Testosterone / Q000378:metabolism*
D013196:Dihydrotestosterone; D013739:Testosterone; D004958:Estradiol