Corbier P, Roffi J, Rhoda J
Physiol Behav. 1983 Apr;30(4):613-6. doi: 10.1016/0031-9384(83)90229-9.
In the male rat, a dramatic increase in serum testosterone occurs during the first four hours of postnatal life. The experiments sought to determine whether such an increase would participate directly on the defeminization process. Newborn male rats were castrated either at 0 hr in utero (literally at the moment of birth) or at 6 or 12 hrs after birth. Some males were castrated at 0 hr in utero and injected at the time of surgery with 1 or 5 micrograms testosterone propionate (TP). At about 90 days of age, each animal was injected with estrogen and progesterone and tested for female sex behavior. Males castrated at 0 hr in utero displayed typical female sex behavior. Males castrated at 6 or 12 hrs after birth were less receptive than males castrated at 0 hr. Males castrated at 0 hr and injected with testosterone at this time almost never showed lordosis as adults after treatment with ovarian hormones. These results are consistent with the idea that the rapid elevation in serum testosterone which occurs shortly after birth suppresses the development of sexual behavior sensitivity to ovarian hormonal stimulation.
在雄性大鼠中，出生后最初四小时内血清睾酮会急剧增加。这些实验旨在确定这种增加是否会直接参与去雌性化过程。新生雄性大鼠在子宫内0小时（实际上就是出生时）或出生后6或12小时被阉割。一些雄性大鼠在子宫内0小时被阉割，并在手术时注射1或5微克丙酸睾酮（TP）。在大约90日龄时，每只动物都注射雌激素和孕酮，并测试其雌性性行为。在子宫内0小时被阉割的雄性大鼠表现出典型的雌性性行为。出生后6或12小时被阉割的雄性大鼠比在子宫内0小时被阉割的雄性大鼠接受性更低。在子宫内0小时被阉割并在此期间注射睾酮的雄性大鼠，在接受卵巢激素治疗后成年后几乎从不表现出脊柱前凸。这些结果与以下观点一致：出生后不久血清睾酮的快速升高会抑制对卵巢激素刺激的性行为敏感性的发展。
