在內(nèi)分泌系統(tǒng)中,，腦垂體是無可爭辯的冠軍,。研究發(fā)現(xiàn),，它能夠比其他任何結(jié)構(gòu)更加有力地控制身體的生長,。日本一研究團隊在美國《國家科學(xué)院院刊》（PNAS）上在線報道了此項成果。
不過現(xiàn)在,，一個新的競爭者已經(jīng)踏入了這場冠軍的爭奪戰(zhàn),，雖然其手段有欠正當(dāng)。
科學(xué)家們首次發(fā)現(xiàn),，至少在莫桑比克羅非魚中,，生殖腺扮演了“二級垂體”的角色，可以幫助魚類長到成年個頭,。
這些生殖器官能夠使雄性魚產(chǎn)生精子,，雌性魚產(chǎn)生卵細(xì)胞。如果沒有它們,，這些魚只能長到其普通大小的幾分之一,。
研究人員發(fā)現(xiàn)，將生殖腺移植回羅非魚的體內(nèi),，甚至是移植到一些無關(guān)緊要的部位諸如魚的背脊,，都能使這些魚重新開始生長。
該研究小組報道稱,，這些發(fā)現(xiàn)或許適用于所有的脊椎動物，包括人類在內(nèi),。
同時,，這些發(fā)現(xiàn)對漁業(yè)來說也是一個福音。現(xiàn)在,，養(yǎng)殖戶們一直想盡各種辦法,，在養(yǎng)殖的魚未長到可以作為食物前，不讓魚類進(jìn)行繁殖,。（生物谷Bioon.com）
doi:10.1073/pnas.1118704109
PMC:
PMID:
Gonads directly regulate growth in teleosts
Sandip Bhattaa, Toshiharu Iwaia, Chiemi Miuraa, Masato Higuchia, Sonoko Shimizu-Yamaguchia, Haruhisa Fukadab, and Takeshi Miuraa
In general, there is a relationship between growth and reproduction, and gonads are known to be important organs for growth, but direct evidence for their role is lacking. Here, using a fish model, we report direct evidence that gonads are endocrine organs equal to the pituitary in controlling body growth. Gonadal loss of function, gain of function, and rescue of growth were investigated in tilapia. Gonadectomy experiments were carried out in juvenile males and females. Gonadectomy significantly retarded growth compared with controls; however, this retardation was rescued by the implantation of extirpated gonads. Because gonads express growth hormone, it is possible that gonads control body growth through the secretion of growth hormone and/or other endocrine factors. We propose that gonads are integral players in the dynamic regulation of growth in teleosts.
