據(jù)8月22日的《科學》(Science)雜志報告說,,哺乳類動物的鼻子含有一種專門的傳感器,,它能察覺到由同伴動物發(fā)出的化學性的警示信號。這種所謂的“Grueneberg神經(jīng)節(jié)”是位于鼻尖附近的一個由圓形細胞組成的緊湊的球體,。這種神經(jīng)節(jié)是在1973年被發(fā)現(xiàn)的,,但它的功能是什么則一直存在著爭議,。
Julien Brechbühl及其同事發(fā)現(xiàn),Grueneberg神經(jīng)節(jié)可以捕捉到由相同種系的其它成員在處于危難時所產(chǎn)生的警示性的信息素,。這些種系包括植物,、魚類、昆蟲,,而哺乳動物已知也會發(fā)出這些信息素,。但是人們一直不清楚這些化合物究竟是什么,它們是如何產(chǎn)生的以及它們是如何被探查到的,。研究人員將正常的小鼠與缺乏Grueneberg神經(jīng)節(jié)的小鼠對由其它小鼠所分泌的警示性信息素究竟是如何反應的進行了比較,。那些正常小鼠停止了對其籠子的探索并在籠子的一個角落呆愣著,而其它的小鼠則繼續(xù)在籠子內(nèi)轉(zhuǎn)悠,,好像并不知道危險信號的存在,。可是,,這兩組小鼠都能夠嗅查到埋藏在籠子草墊下的曲奇餅,,這表明它們嗅覺系統(tǒng)的其它功能都是正常的。文章的作者還使用了電子顯微鏡來研究這種神經(jīng)節(jié)的形態(tài)學,。他們確定這些神經(jīng)節(jié)與其它的嗅覺神經(jīng)元有著類似的特征,。(生物谷Bioon.com)
生物谷推薦原始出處:
Science,Vol. 321. no. 5892, pp. 1092 - 1095,,Julien Brechbühl,,Marie-Christine Broillet
Grueneberg Ganglion Cells Mediate Alarm Pheromone Detection in Mice
Julien Brechbühl, Magali Klaey, Marie-Christine Broillet*
Alarm pheromones (APs) are widely used throughout the plant and animal kingdoms. Species such as fish, insects, and mammals signal danger to conspecifics by releasing volatile alarm molecules. Thus far, neither the chemicals, their bodily source, nor the sensory system involved in their detection have been isolated or identified in mammals. We found that APs are recognized by the Grueneberg ganglion (GG), a recently discovered olfactory subsystem. We showed with electron microscopy that GG neurons bear primary cilia, with cell bodies ensheathed by glial cells. APs evoked calcium responses in GG neurons in vitro and induced freezing behavior in vivo, which completely disappeared when the GG degenerated after axotomy. We conclude that mice detect APs through the activation of olfactory GG neurons.