The Action of the Sex Pheromones in Urodele

一种肽信息素（Sodefrin）和一些甾体信息素候选物，雄烯二酮和双烯醇酮，从雄性蝾螈的腹部腺体分泌。雄烯二酮和双烯醇酮都能吸引性发育成熟的雌性。当亚阈值量的雄烯二酮和双烯醇酮与sodefrin组合使用时，它们显著增强了sodefrin的雌性吸引活性。雌性对这两种类固醇的偏好被证明可以通过堵塞双侧鼻孔而完全消除，这表明这些类固醇作用于嗅觉器官。为了确定腹侧鼻上皮中的嗅觉受体细胞对这些类固醇的敏感性，记录嗅觉电图（EOG）。在性发育的雌性中，犁鼻上皮对类固醇的反应比主要的嗅觉上皮大。用催乳素和促性腺激素处理的性发育雌性和未发育雌性的EOG反应显著大于用催乳素处理的雄性或未处理的雌性。得出的结论是，这些类固醇的主要作用部位位于犁鼻上皮，并且该区域对类固醇的敏感性是性别和激素依赖性的。

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.