雄性布氏田鼠包皮腺中的昆虫信息素类似物编码的性别和个体信息

摘要

我们利用二氯甲烷抽提和气质联用(GC-MS)比较分析了正常和阉割布氏田鼠的包皮腺分泌物(PGS)成分.我们检测到33个成分,它们几乎在所有的被测布氏田鼠都存在,其中27个成分以前报道为昆虫的信息素组分.睾丸切除不能使任何一个成分完全消失,但是显著降低了10个首先从GC-MS流失出的小分子成分,即7个饱和与不饱和的乙酸酯,一个饱和六酸酯和两个饱和八酸酯, 其中,包括PGS含量最高的成分E,E-法尼醇乙酸酯.因此,可以认为这些受睾丸调节的成分为雄性信息素的候选成分.对雌鼠的嗅觉双项选择测定说明低浓度的PGS和法尼醇乙酸酯水溶液对雌性有吸引作用,而高浓度时都具有趋避作用.这说明PGS具有剂量依赖的性吸引作用,法尼醇乙酸酯是一种剂量依赖的雄性信息素.进一步的数量比较说明,所有检测到成分的百分组成在个体间表现出巨大的个体变异,说明PGS的成分有个体的特异性,可能传递个体的嗅觉信息.%We analyzed the volatile composition of dichloromethane extracts of preputial glandular secretions (PGS) from intact and castrated male Brandt's voles Lasiopodomys brandtii by using gas chromatography-mass spectrometry (GC-MS).Thirty-three volatile compounds were detected and were present in nearly all scent donors; 27 had previously been reported as insect pheromone components. Castration did not eliminate any compounds; however, it significantly suppressed the relative quantity of ten early-eluting, low molecular weight components. These included seven saturated and unsaturated acetates, one hexanoate, and two saturated octanoates. In particular, E,E-Farnesyl acetate (FA) was the most abundant compound in the PGS. We suggest that FA and other components might be candidates for male-produced pheromones. Two-choice behavioral assays of females revealed that low concentrations of raw PGS (0.056%) and E,E-farnesyl acetate (FA) (5 parts per million in water v/w) were attractive, whereas high concentrations (0.56% and 50 parts per million, respectively) were repellent. This suggested that FA may act as a male pheromone in a dosage-dependent manner. Extremely high variability of the relative quantities of almost all detected compounds among individuals indicated the inter-individual dissimilarities of PGS and consequent possibilities to communicate individuality to other conspecific members.