The Action of the Sex Pheromones in Urodele

雄性虎尾蛇的腹腺分泌一种多肽信息素(索德林)和一些类固醇信息素候选者雄烯二酮和孕烯醇酮。雄烯二酮和孕烯醇酮都吸引了性发育的雌性。当阈值以下剂量的雄烯二酮和孕烯醇酮与硫氰菊酯联合使用时，它们显著增强了硫氰菊酯的引诱活性。雌性对这两种类固醇的偏爱通过堵塞双侧鼻孔被完全消除，这表明这些类固醇作用于嗅器官。为了确定鼻腹侧上皮嗅觉感受器细胞对这些激素的敏感性，记录了嗅电图(EOGs)。在性发育的女性中，犁鼻上皮对类固醇的反应比主嗅觉上皮更强。用催乳素和促性腺激素治疗的性发育女性和未发育女性的EOG反应明显大于激素治疗的男性或未治疗的女性。结论是，这些类固醇的主要作用部位位于犁鼻上皮，该区域对类固醇的敏感性与性别和激素有关。

A peptide pheromone (Sodefrin) and some steroidal pheromone candidates, androstenedione and pregnenolone, are secreted from the abdominal glands of the male newts,Cynops pyrrhogaster. Both androstenedione and pregnenolone attracted the sexually developed females. When subthreshold amounts of androstendione and pregnenolone were applied in combination with sodefrin, they significantly enhanced the female-attracting activity of sodefrin. The preference of the females for both steroids was shown to be completely abolished by plugging the bilateral nostrils, indicating that these steroids act on the olfactory organ. In order to determine the sensitivity of the olfactory receptor cells in the ventral nasal epithelium to these steroids, electro-olfactograms (EOGs) were recorded. In the sexually developed females, the vomeronasal epithelium showed a great response to the steroids than the main olfactory epithelium. The EOG response of sexually developed females and undeveloped females treated with prolactin and gonatotropin was significantly greater than those of the hormone-treated males or untreated females. It was concluded that the main site of action of these steroids resides in the vomeronasal epithelium and that sensitivity to the steroids in this region is sex- and hormone- dependent.