[Effect of interleukin-2 on the proliferation of cultured rat anterior pituitary cells].

The present study was to investigate whether IL-2 is involved in the proliferation control of anterior pituitary (AP) cells. Primary culture of AP cells was obtained from either male or female Sprague-Dawley rats. The effects of IL-2 were assessed by 3H-thymidine incorporation rate. It was found that: (1) IL-2 (10-500 U/ml) significantly stimulated 3H-TdR incorporation into AP cells of female pregnant as well as none-pregnant rats, but inhibited 3H-TdR incorporation in the male rats. (2) The stimulatory effect of IL-2 was reversed in overiectomized rats, but could be restored when the overiectomized rats were treated with estradiol benzoate (5 micrograms/d per rat). (3) When the male rats were orchiectomized for 2 weeks, the inhibitory effects of IL-2 did not occur. The above data indicated that the proliferative effect of IL-2 on AP is a joint action of sex steroids hormones.