科学家发现：支配雄性仓鼠具有交配欲望的化学物质与促使人类进入青春期的化学物质相同。
印第安那州立大学的Greg Demas和他的同事们发现缩氨酸转移抑制素控制着西伯利亚仓鼠(Phodopus sungorus)的生育，这种仓鼠只在夏季繁殖。在冬季，雄性仓鼠则改变了体色，缩回性腺、没有性欲。而转移抑制素也是促使人类进入青春期的关键因素之一。
研究人员们将一组试验用雄性仓鼠暴露于类似于漫长的夏季气候长达八周，而另外一组则暴露于短暂的、类似于冬天的气候。接着，Demas和他的科研小组检测了与仓鼠生殖行为有关的大脑部分的转移抑制素含量。结果发现：那些暴露于夏季条件的仓鼠明显地比那些暴露于人造冬季条件的仓鼠生殖欲望活跃、而且转移抑制素含量也更高。科学家们还发现给那些“沉浸”于冬季的仓鼠注射转移抑制素也会唤起它们的性欲。
该项研究结果发表在1月22日的《新科学家》杂志上。 （ Newscientist）
部分英文原文：
Chemical trigger for reproduction
Male hamsters' urge to mate is switched on by the same chemical that triggers puberty in humans.
Greg Demas at Indiana University in Bloomington and his colleagues found that the peptide kisspeptin is involved in switching fertility on and off in Siberian hamsters (Phodopus sungorus), which only breed in summer. In winter, male hamsters change colour, their gonads retract and they have no libido. Kisspeptin is one of the triggers for human puberty (New Scientist, 22 July 2006, p 34).
One group of male hamsters was exposed to eight weeks of long, summer-like days and another group to short, winter-like days. Demas and his team then measured the amount of kisspeptin in a part of the brain involved in reproductive behaviour.
Those animals that had been exposed to long days were reproductively active and had significantly more kisspeptin than those that had been through an artificial winter. An injection of kisspeptin was also enough to relaunch fertility in the "winter" hamsters (Endocrinology, DOI: 10.1210/en.2006-1249).
