Influence of phytoestrogens on development of reproductive functions

本实验研究了植物雌激素香豆酚、染料木素和白藜芦醇对大鼠性分化和生殖行为的影响。植物雌激素对脑功能男性化的影响(1)香豆素(CM)的作用：生后第5天单次注射3 mg CM可引起雌性大鼠阴道开放加速，阴道涂片出现无环性改变，卵巢小而无黄体，前额活动减少，注射雌二醇1 mg。白藜芦醇的作用：生后第5天单次注射5 mg白藜芦醇可引起少数大鼠阴道涂片出现非周期性改变，而大多数雌性大鼠则无此改变。注射黄体酮不影响前凸活动。(3)孕酮预防库美斯特罗的男性化作用：孕酮可以抑制大脑中雌激素的功能。在本实验中，出生后第5天同时注射3 mg CM和0.5 mg孕酮对雌性幼鼠的阴道张开、阴道涂片和前凸活动没有影响。这说明孕酮也能阻止植物雌激素的雄性化作用。植物雌激素对成年雌性大鼠前凸和母体行为的影响。(1)性行为：去卵巢大鼠在注射CM 44h后，注射CM 1 mg和孕酮0.5 mg，观察其行为。结果，没有观察到任何影响。(2)母体行为：去卵巢大鼠每日注射苯甲酸雌二醇1 mg，可加速母体行为的发生，而去卵巢大鼠的LMG CM则无此作用。这些结果表明，植物雌激素对成年雌性大鼠的生殖行为无促进作用，但对新生大鼠的大脑发育有促进作用。

In this experiment, effects of phytoestrogens, coumestrol, genistein and resveratrol, on sexual differentiation and reproductive behaviors were examined in the rat.1. Effects of phytoestrogens on masculinization of the brain functions(1) Effects of coumestrol(CM) : Single injection with 3mg CM on day 5 after birth induced acceleration of vaginal opening, acyclic change in vaginial smear, small ovaries without corpus luteum and low lordotic activity in female rats, as injection with 1mg estradiol. On the other hand, no effects were observed when injected with genistein.(2) Effects of resveratrol(RTL) : Single injection with 5mg RTL on day 5 after birth induced acyclic change in vaginal smear in a few rats, but not in most female rats. Lordotic activity was not influenced by injection with RTL.(3) Prevention of masculinizing effects of coumestrol by progesterone : Progesterone is known to suppress functions of estrogen in the brain. In this experiment, simultaneous injection with 3mg CM and 0.5mg progesterone to female pups on day 5 after birth induced no effect on vaginal opening, vaginal smear and lordotic activity. This indicates that progesterone also can prevent masculinizing effect of phytoestrogens.2. Effects of phytoestrogens on lordosis and maternal behavior in adult female rats.(1) Sexual behavior : Ovariectomized rats were injected with 1mg CM and 0.5mg progesterone 44 hrs after injection of CM and lordosis behavior was observed. As a result no effects were observed. No effects were observed even when injected those in ovariectomized rats treated of substhresthold dose of estrogen.(2) Maternal behavior : Injections with 1mg estradiol benzoate daily for 10 days accelerated onset of maternal behavior but lmg CM in ovariectomized rats did not.These results indicate that phytoestrogen is effective in mascuilinizing the brain in the neonatal period but not in facilitation of reproductive behaviors in adult female rats.