[Changes in the concentration of luteinizing hormone in the blood serum and of luliberin in the hypothalamus of castrated rats after the administration of testosterone and its 5 alpha-reduced metabolites. I].

Luteinizing hormone concentration in the blood serum and luliberin content in the hypothalamic arcuate body and medial eminence were determined in castrated mature rats 1, 3, 6, 12, 24 hours afte single injections of testosterone and its 5 alpha-reduced metabolites (dihydrotestosterone, 5 alpha-androstane-3 alpha, 17 beta-diol and 5 alpha-androstane-3 beta, 17 beta-diol) at a dose of 2.5 x 10(-7) kg/kg body weight by radioimmunoassay. Principal differences between testosterone and its 5 alpha-reduced metabolite action on the hypothalamohypophyseal system were detected from the stand point of their effectiveness and the effect realization rate.