Slob A K, Bogers H, van Stolk M A
Behav Brain Res. 1981 May;2(3):347-62. doi: 10.1016/0166-4328(81)90017-6.
Two experiments were carried out to investigate the contribution of gonadal hormones to the expression of sex differences in open field behaviour of adult female and male rats. In the first experiment rats were gonadectomized or sham-operated in adulthood and tested in the open field 1, 2, 3, 4, 5 or 6 weeks later (3 min/rat on 3 consecutive days during the light period of the day). It was found that following gonadectomy the well known sex difference in ambulation and rearing behaviour (females more than males), as well as in defaecation (females less than males) remained. Ovariectomy caused a decrease in ambulation and rearing, with an increase in defaecation, whereas castration had no significant effect on ambulation and rearing, but also increased defaecation. Also an overall increase in ambulation and rearing was found: animals tested 5 and 6 weeks following the operation were significantly more active than animals tested at 1-4 weeks after the operation. In the second experiment female and male rats were gonadectomized and 7 weeks later they received a silastic implant containing testosterone (T), dihydrotestosterone (DHT), oestradiol (E2), DHT plus E2, or nothing (control condition). Four weeks after the implantation the animals were tested in the open field (3 min/rat on 3 consecutive days). An overall sex difference was found for ambulation (females more than males) and for defaecation (females less than males). The only effect of hormone administration was found in DHT-treated animals: lowest ambulation and highest defaecation compared to other hormone and control animals. No differences were found between the T, E2, DHT plus E2, and control animals. From these data it was concluded that endogenous gonadal steroids seem to play a minor role in the expression of sex differences in adult open field behaviour in the rat.
进行了两项实验，以研究性腺激素对成年雌性和雄性大鼠旷场行为中性别差异表达的作用。在第一个实验中，大鼠在成年期进行去势或假手术，并在1、2、3、4、5或6周后在旷场中进行测试（在白天的光照期连续3天，每只大鼠测试3分钟）。结果发现，去势后，在行走和竖毛行为（雌性多于雄性）以及排便（雌性少于雄性）方面，众所周知的性别差异依然存在。卵巢切除导致行走和竖毛减少，排便增加，而阉割对行走和竖毛没有显著影响，但也增加了排便。还发现行走和竖毛总体上有所增加：术后5周和6周测试的动物比术后1 - 4周测试的动物明显更活跃。在第二个实验中，对雌性和雄性大鼠进行去势，7周后给它们植入含有睾酮（T）、双氢睾酮（DHT）、雌二醇（E2）、DHT加E2或无植入物（对照条件）的硅橡胶管。植入后4周，动物在旷场中进行测试（连续3天，每只大鼠测试3分钟）。在行走（雌性多于雄性）和排便（雌性少于雄性）方面发现了总体性别差异。激素给药的唯一影响在接受DHT治疗的动物中发现：与其他激素和对照动物相比，行走最少且排便最多。在T、E2、DHT加E2和对照动物之间未发现差异。从这些数据得出结论，内源性性腺类固醇似乎在大鼠成年旷场行为的性别差异表达中起次要作用。
