Effect of alpha 2u-globulin on serum concentration of gonadotrophins and testicular activity in oestrogen-treated rats.

Adult male rats were given injections of oestradiol-17 beta (50 micrograms/100 g body wt per day) for 7 days. When they were killed 14 days after the last injection, serum levels of gonadotrophins and testosterone and weights of accessory sex organs were less, testicular 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) activity was suppressed and spermatogenesis was inhibited. Administration of alpha 2u-globulin (1.5 mg/day) for 14 days to oestrogen-treated rats and for 10 days to control rats resulted in increased concentrations of gonadotrophins and testosterone in the serum. Accessory sex organ weight and spermatogenesis appeared to be normal while 17 beta-HSD activity increased in oestrogen-treated rats after treatment with alpha 2u-globulin. It was concluded that alpha 2u-globulin has an effect on testicular function in oestrogenized rats by inducing gonadotrophin and testosterone synthesis.