Department of Physiology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo, Tokyo 113-8602, Japan.
Horm Behav. 2011 Jan;59(1):193-9. doi: 10.1016/j.yhbeh.2010.11.011. Epub 2010 Nov 20.
Both volatile and nonvolatile molecules are involved in chemosensory communication in rodents. Volatile odors from physically inaccessible estrous females induced increased numbers of c-Fos-positive cells in the preoptic area (POA) and in the cortical nucleus of the amygdala (CoA) of male rats. The numbers of c-Fos-positive cells in the medial nucleus of the amygdala (MeA) increased in response to the nonvolatile odors of bedding soiled with the excreta of estrous females. In an alternate choice paradigm, male rats carrying ibotenic acid lesions in either the MeA or the CoA--or a combination of both--distinguished the odors of estrous females from those of males, although the time spent sniffing the stimuli was diminished. Males with POA lesions showed complete loss of this capability. Males carrying either of the lesions did not detect differences between estrous and anestrous females or between intact and orchidectomized males. Lesions in the POA or MeA severely impaired male sexual behavior, whereas a CoA lesion had no effects. Thus, c-Fos-positive cells in the CoA might be involved in chemosensory transmission relevant to certain social contexts, but not in the execution of male sexual behavior. The POA is indispensable for both olfactory preferences and sexual behavior. The residual olfactory preference in males with MeA or CoA lesions or the combination of both could reflect an additional route for chemosensory transmission from the main olfactory bulb to the POA.
挥发性和非挥发性分子都参与了啮齿动物的化学感觉通讯。来自无法接触的动情期雌性的挥发性气味会诱导雄性大鼠的前脑区（POA）和杏仁皮质核（CoA）中 c-Fos 阳性细胞的数量增加。非挥发性气味来自动情期雌性排泄物污染的垫料，会导致杏仁中核（MeA）的 c-Fos 阳性细胞数量增加。在交替选择范式中，携带 MeA 或 CoA 内的（或两者的组合）IBO 损伤的雄性大鼠能够区分动情期雌性和雄性的气味，尽管嗅探刺激的时间减少了。POA 损伤的雄性完全丧失了这种能力。携带任何一种损伤的雄性都无法检测到动情期和非动情期雌性之间或完整和去势雄性之间的差异。POA 或 MeA 的损伤严重损害了雄性的性行为，而 CoA 的损伤则没有影响。因此，CoA 中的 c-Fos 阳性细胞可能参与了与某些社交环境相关的化学感觉传递，但不参与执行雄性性行为。POA 对嗅觉偏好和性行为都是不可或缺的。MeA 或 CoA 损伤或两者组合的雄性仍然存在的嗅觉偏好可能反映了从主嗅觉球到 POA 的化学感觉传递的另一种途径。
