中國科學(xué)院動物研究所等單位的科學(xué)家最近從模式動物——小鼠的特化氣味腺(包皮腺和陰蒂腺)中發(fā)現(xiàn)兩個新的半揮發(fā)性信息素分子(16碳醇和16醇乙酸脂),，并證明它們具有劑量依賴的,、雙相性吸引效應(yīng),。此發(fā)現(xiàn)是該組研究人員在他們?nèi)ツ晖贫ǖ亩鄠€小鼠性信息素成分(Chemical Senses 32:293-303)的基礎(chǔ)上,，進(jìn)一步對其功能測定的結(jié)果。
這兩個過去未被報道的主要氣味成分為雌雄共享,，但在雄鼠中的含量顯著高于雌性,，而且對睪丸有依賴性；將合成的16碳醇和16醇乙酸脂按分泌到雄鼠尿液的生理濃度(高濃度)加入閹割雄鼠的尿液,，對雌鼠產(chǎn)生吸引作用,，說明它們是雄性信息素；同時,，切除犁鼻器(VNO)的雌鼠對這兩個成分的偏好消失,，這種VNO依賴性的性吸引作用，進(jìn)一步說明它們是小鼠的雄性信息素,；但是,，當(dāng)這兩個成分同時按生理水平加入閹割雄鼠的尿液時，才能表現(xiàn)出顯著的性吸引作用,；如果只用其中之一則需要高出生理濃度很多,，才能有性吸引效應(yīng)，說明這兩個成分是有增效作用(synergism)的雄性信息素成分,。出乎預(yù)料的是,，這兩個成分以接近雌鼠尿液中的生理含量(低濃度)，加入閹割雄鼠尿液,，則對雄鼠產(chǎn)生性吸引作用,，說明這兩個雌雄鼠氣味腺共有的成分具有劑量依賴的反向效應(yīng)的性吸引作用。用其水溶液進(jìn)行測試也表現(xiàn)出同樣的效果,。最近的實驗又證明雄鼠對這兩個成分的反應(yīng)也是VNO依賴的,。另外，北京生命科學(xué)研究所羅敏敏實驗室的腦神經(jīng)反應(yīng)測試也說明它們可以激活雌性小鼠副嗅球,、主嗅球,、杏仁體和下丘腦的c-Fos反應(yīng)，再次從神經(jīng)生物學(xué)角度確認(rèn)了它們的信息素身份,。
小鼠信息素的化學(xué)研究已有30多年,，國外報到了8個揮發(fā)性信息素成分。該研究在小鼠的信息素成分譜中添加了兩個主要成分,，也首次闡明雌小鼠吸引雄小鼠的信息素,，并闡明了哺乳動物利用雌雄共享氣味成分的劑量差異來傳遞性別信息的編碼特點。另外,，小鼠和全球分布最廣的害鼠－小家鼠為同種,，這兩個低揮發(fā)性的雙相信息素可能在鼠害控制中有一定的應(yīng)用潛力。
主要成果于7月9日在國際行為神經(jīng)科學(xué)學(xué)會(IBNS)官方雜志——愛思唯爾期刊《生理與行為》（Physiology and Behaviour）在線發(fā)表,。三個審稿人認(rèn)為,，該論文在堅實的GC-MS分析基礎(chǔ)上，對兩個新的信息素成分的特性進(jìn)行了扼要探索,，是原創(chuàng)性的,，對增加哺乳動物氣味及性別和個體識別的知識做出了貢獻(xiàn)。
該論文作者為張健旭,、劉瑩娟,、張進(jìn)華和孫立新，得到國家基金委面上項目,，科學(xué)院創(chuàng)新項目和科技部攻關(guān)項目的資助,。（生物谷Bioon.com）
生物谷推薦原始出處：
Physiology and Behaviour，doi:10.1016/j.physbeh.2008.07.002,，Jian-Xu Zhang, Ying-Juan Liu, Jin-Hua Zhang and Lixing Sun
Dual role of preputial gland secretion and its major components in sex recognition of mice
Jian-Xu Zhanga, Ying-Juan Liua, Jin-Hua Zhanga and Lixing Sunc
aState Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China bSchool of Biological Sciences, Beijing Forestry University, Beijing 100083, China cDepartment of Biological Sciences, Central Washington University, Ellensburg WA98926-7537, USA
Abstract
This study was aimed at validating the sexual attractiveness of hexadecanol and hexadecyl acetate, two putative pheromone compounds, from preputial gland secretion of mice. These two compounds have been reported to be among the major components of preputial gland secretion in both sexes but higher in quantity in males than females. In this study, we show that castration suppressed the production of the two compounds, further suggesting their association with maleness. Adding preputial gland secretion and the synthetic analogs of the two compounds to castrated male urine at their physiological levels in intact males increased the attractiveness of castrated male urine to female mice, showing that the two compounds were indeed male pheromones. Furthermore, their sexual attractiveness disappeared upon removing the vomeronasal organs (VNOs) from female recipients. Replenishing castrated male urine with preputial gland secretion and the two compounds at their physiological levels in females increased the attractiveness of castrated male urine to males. Such a reversal of sexual attractiveness for hexadecanol and hexadecyl acetate suggests that they had opposing dual effects in sexual attractiveness in a dosage-dependent manner.
