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

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。

Gender and individual information coded by insect pheromone analogs in the preputial glands in male brandt's voles Lasiopodomys brandtii

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.