Albert D J, Walsh M L, Gorzalka B B, Siemens Y, Louie H
Physiol Behav. 1986;36(3):401-7. doi: 10.1016/0031-9384(86)90305-7.
Alpha male rats from mixed sex colony groups were tested for aggressiveness toward nonaggressive male intruders. Afterward, they were castrated and implanted with testosterone filled Silastic tubes, castrated and implanted with empty tubes, or sham castrated and implanted with empty tubes. There were significant declines in the aggressiveness (lateral attacks, bites, and piloerection but not on-top) of castrated rats without testosterone replacement but not in castrated rats with testosterone replacement. At a second operation, castrated animals had their testosterone capsules removed or had their empty capsules replaced with testosterone filled capsules. When tested for aggression toward nonaggressive intruders, those alpha males which had testosterone removed declined in aggressiveness while those which had it implanted returned to a level of aggressiveness close to that emitted by sham castrated control animals. Subordinate males became dominant when alpha males were castrated and not given testosterone replacement. In a final series of observations, sham castrated males were found to be more aggressive than castrated males when pitted against one another. It is argued that testosterone plays a primary role in intermale social aggression and that the decline in aggressiveness following castration is typically accompanied by a loss of social dominance.
来自混合性别群体的雄性首领大鼠接受了对非攻击性雄性入侵者的攻击性测试。之后，它们被阉割并植入填充睾酮的硅橡胶管，或者被阉割并植入空管，或者进行假阉割并植入空管。未进行睾酮替代的阉割大鼠的攻击性（侧攻、撕咬和竖毛，但不包括骑跨行为）显著下降，但进行了睾酮替代的阉割大鼠则没有。在第二次手术中，阉割动物的睾酮胶囊被取出，或者将空胶囊换成填充睾酮的胶囊。当测试对非攻击性入侵者的攻击性时，那些睾酮被取出的雄性首领的攻击性下降，而那些植入睾酮的雄性首领则恢复到接近假阉割对照动物所表现出的攻击性水平。当雄性首领被阉割且未进行睾酮替代时，从属雄性会变得占主导地位。在最后一系列观察中，发现假阉割雄性在相互对抗时比阉割雄性更具攻击性。有人认为，睾酮在雄性间的社会攻击中起主要作用，阉割后攻击性的下降通常伴随着社会主导地位的丧失。
