Albert D J, Dyson E M, Walsh M L
Physiol Behav. 1987;39(5):555-60. doi: 10.1016/0031-9384(87)90153-3.
Male hooded rats were castrated, subcutaneously implanted with testosterone-filled silastic tubes, and individually housed with an intact adult female rat. An unfamiliar male intruder was introduced into each colony on a weekly basis and the aggressive behavior of the resident male was recorded. When the intermale social aggressive behavior of the resident male toward the intruder reached a high level in terms of a composite aggression score, the subcutaneous testosterone tubes were removed. Weekly tests of aggression toward unfamiliar intruders continued until the aggression of the resident male dropped to a low level for two successive weeks in terms of our composite aggression score. Bilateral implants of pellets of testosterone propionate were then made into the medial hypothalamus or adjacent tissue. A control group was implanted with cholesterol pellets into the medial hypothalamus. During four weekly tests following the implant, rats with testosterone propionate implants in the medial hypothalamus showed increases in lateral attacks, lateral attack duration, bites, and piloerection. The increase in aggression was not consistently displayed by animals with testosterone propionate implants dorsal or anterior to the medial hypothalamus or by animals with cholesterol implants in the medial hypothalamus. These results suggest that the medial hypothalamus or closely adjacent tissue contains testosterone-sensitive neural circuitry modulating intermale social aggression.
雄性有头罩大鼠被阉割，皮下植入充满睾酮的硅橡胶管，并与一只成年雌性大鼠单独饲养在一起。每周向每个鼠群中引入一只陌生的雄性入侵者，并记录常住雄性大鼠的攻击行为。当常住雄性大鼠对入侵者的雄性间社会攻击行为在综合攻击得分方面达到高水平时，皮下睾酮管被移除。每周对陌生入侵者的攻击测试持续进行，直到常住雄性大鼠的攻击行为在我们的综合攻击得分方面连续两周降至低水平。然后将丙酸睾酮丸双侧植入内侧下丘脑或相邻组织。对照组在内侧下丘脑植入胆固醇丸。在植入后的四周每周测试中，内侧下丘脑植入丙酸睾酮的大鼠在侧向攻击、侧向攻击持续时间、撕咬和竖毛方面有所增加。在内侧下丘脑背侧或前方植入丙酸睾酮的动物或在内侧下丘脑植入胆固醇的动物并没有持续表现出攻击行为的增加。这些结果表明，内侧下丘脑或紧密相邻的组织含有调节雄性间社会攻击行为的睾酮敏感神经回路。
