Brennan P A, Hancock D, Keverne E B
Sub-Department of Animal Behaviour, University of Cambridge, U.K.
Neuroscience. 1992 Jul;49(2):277-84. doi: 10.1016/0306-4522(92)90095-j.
Female mice form a memory for the pheromones of the male with which they mate. It has been proposed that the site of the synaptic changes underlying this memory is the accessory olfactory bulb, at the first level of the accessory olfactory system. In this study we have examined the expression of the immediate-early genes c-fos, c-jun and egr-1 in the mitral and granule cells of the accessory olfactory bulb immediately after mating, during the period of memory formation. Transient increases were seen in the number of granule cell nuclei expressing c-fos and the number of granule and mitral cell nuclei expressing egr-1, during the period of memory formation. No changes were observed in the expression of c-jun during this period. The increase in the number of cells expressing c-fos and egr-1 required the association of mating and pheromonal exposure, conditions also required for memory formation. Large increases in the number of mitral and granule cell nuclei expressing c-fos and egr-1 were also observed following the infusion of the drug bicuculline into the accessory olfactory bulb in the absence of mating. This procedure has previously been shown to result in the formation of a nonspecific memory for male pheromones. These results associate the expression of c-fos and egr-1 in the accessory olfactory bulb with the conditions required for the formation of an olfactory memory for male pheromones.
雌性小鼠会对与之交配的雄性小鼠的信息素形成记忆。有人提出，这种记忆背后突触变化的位点是副嗅球，它位于副嗅觉系统的第一级。在本研究中，我们检测了在记忆形成期间，交配后即刻副嗅球的二尖瓣细胞和颗粒细胞中即早基因c-fos、c-jun和egr-1的表达情况。在记忆形成期间，表达c-fos的颗粒细胞核数量以及表达egr-1的颗粒细胞和二尖瓣细胞核数量出现短暂增加。在此期间，未观察到c-jun表达的变化。表达c-fos和egr-1的细胞数量增加需要交配和信息素暴露的关联，而这也是记忆形成所必需的条件。在未交配的情况下，向副嗅球注射荷包牡丹碱后，也观察到表达c-fos和egr-1的二尖瓣细胞和颗粒细胞核数量大幅增加。此前已证明，该操作会导致对雄性信息素形成非特异性记忆。这些结果将副嗅球中c-fos和egr-1的表达与形成雄性信息素嗅觉记忆所需的条件联系起来。
