Testosterone programs adult social behavior before and during, but not after, adolescence.
Testosterone programs adult social behavior before and during, but not after, adolescence.
复制标题
DOI：
10.1210/en.2008-1708
复制
发表时间：
2009-08
期刊：
影响因子：
4.8
通讯作者：
Kalynn M. Schulz;J. L. Zehr;Kaliris Y. Salas-Ramirez;C. Sisk
中科院分区：
文献类型：
--
作者：
Kalynn M. Schulz;J. L. Zehr;Kaliris Y. Salas-Ramirez;C. Sisk
虽然青春期大脑是性腺激素的主要目标，但我们对激素对青少年神经和行为发育的影响的理解仍然有限。这些实验研究了相对于青春期，睾酮（T）暴露时间的变化如何改变雄性叙利亚仓鼠社会行为背后的类固醇敏感神经回路的强度。实验1通过在出生后第10天切除雄性性腺并在青春期之前、期间或之后用SILASTIC品牌T植入物治疗19天来模拟青春期早期、按时和晚期发育。在青春期之前或期间，而不是之后，T治疗促进了成年期的交配行为。此外，青春期前的T治疗最有效地增加了交配行为的整体，表明暴露于青春期激素的时间有助于成年行为的个体差异。实验2研究了青少年T治疗对青少年男性（即仍然preadolescent）的交配神经回路内的行为和大脑区域体积的影响。虽然preadolescent T治疗没有诱导生殖行为的少年男性，它确实增加了体积的床核的终纹，性二形核，posterodorphic内侧杏仁核，posteroventral内侧杏仁核的成人典型的大小。与此相反，青少年前背内侧杏仁核和腹内侧下丘脑的体积没有改变preadolescent T治疗，但显着不同的成年对照组的体积，这表明，在青春期这些大脑区域的进一步成熟是需要男性生殖行为的表达。因此，青少年社会行为的成熟可能涉及类固醇非依赖性和类固醇依赖性过程，青春期标志着出生后对类固醇依赖性大脑组织敏感性的结束。
Whereas the adolescent brain is a major target for gonadal hormones, our understanding of hormonal influences on adolescent neural and behavioral development remains limited. These experiments investigated how variations in the timing of testosterone (T) exposure, relative to adolescence, alters the strength of steroid-sensitive neural circuits underlying social behavior in male Syrian hamsters. Experiment 1 simulated early, on-time, and late pubertal development by gonadectomizing males on postnatal d 10 and treating with SILASTIC brand T implants for 19 d before, during, or after adolescence. T treatment before or during, but not after, adolescence facilitated mating behavior in adulthood. In addition, preadolescent T treatments most effectively increased mating behavior overall, indicating that the timing of exposure to pubertal hormones contributes to individual differences in adult behavior. Experiment 2 examined the effects of preadolescent T treatment on behavior and brain regional volumes within the mating neural circuit of juvenile males (i.e. still preadolescent). Although preadolescent T treatment did not induce reproductive behavior in juvenile males, it did increase volumes of the bed nucleus of the stria terminalis, sexually dimorphic nucleus, posterodorsal medial amygdala, and posteroventral medial amygdala to adult-typical size. In contrast, juvenile anterodorsal medial amygdala and ventromedial hypothalamus volumes were not changed by preadolescent T treatment yet differed significantly in volume from adult controls, suggesting that further maturation of these brain regions during adolescence is required for the expression of male reproductive behavior. Thus, adolescent maturation of social behavior may involve both steroid-independent and -dependent processes, and adolescence marks the end of a postnatal period of sensitivity to steroid-dependent organization of the brain.