McAllan B M
Department of Physiology, University of New England, Armidale, NSW, Australia.
J Reprod Fertil. 1998 Mar;112(2):199-209. doi: 10.1530/jrf.0.1120199.
The life history of Antechinus stuartii, a marsupial, is highly synchronized and culminates in a brief mating period that is followed by complete male mortality. The accessory reproductive tracts of male A. stuartii enlarge in association with testosterone and cortisol hormone concentrations, but this appears to be unrelated to the spermatogenic cycle. The present study examined the effects of testosterone and cortisol on the male reproductive tract. Four groups of adult males from May (when plasma testosterone and cortisol concentrations are low) were given depot injections of testosterone esters or synthetic cortisol in doses that mimic concentrations found in males in the breeding period (August). Males were given either saline, testosterone only, cortisol only, or testosterone plus cortisol. Experimental groups did not differ in the seminiferous tubule morphology. However, the cells from the caudal end of the epididymides of both testosterone groups were considerably hypertrophied compared with males treated with saline or cortisol only. Testosterone treatment significantly increased prostate and bulbourethral gland mass, although addition of cortisol to the testosterone administration diminished this effect. The morphology of the accessory reproductive tract of males treated with either saline or cortisol only was similar to that of untreated males at the same time of year, and the morphology of the accessory reproductive tract of males treated with testosterone plus cortisol was similar to that of untreated males in the breeding season. Like some other marsupials, the spermatogenic cycle in A. stuartii is apparently not correlated with androgen activity, while the accessory reproductive tract is affected by androgens.
有袋动物斯氏狭足袋鼩的生活史高度同步，在短暂的交配期达到顶峰，随后雄性全部死亡。雄性斯氏狭足袋鼩的附属生殖器官会随着睾酮和皮质醇激素浓度的升高而增大，但这似乎与精子发生周期无关。本研究考察了睾酮和皮质醇对雄性生殖道的影响。选取了四组成年雄性（来自五月，此时血浆睾酮和皮质醇浓度较低），分别给它们注射长效睾酮酯或合成皮质醇，剂量模拟繁殖期（八月）雄性体内的浓度。雄性分别注射生理盐水、仅注射睾酮、仅注射皮质醇或同时注射睾酮和皮质醇。各实验组的生精小管形态没有差异。然而，与仅注射生理盐水或皮质醇的雄性相比，两个睾酮组附睾尾端的细胞明显肥大。睾酮处理显著增加了前列腺和尿道球腺的重量，不过在睾酮给药中添加皮质醇会减弱这种效果。仅注射生理盐水或皮质醇的雄性附属生殖器官的形态与同年未处理雄性在同一时间的形态相似，同时注射睾酮和皮质醇的雄性附属生殖器官的形态与繁殖季节未处理雄性的形态相似。与其他一些有袋动物一样，斯氏狭足袋鼩的精子发生周期显然与雄激素活性无关，而附属生殖器官则受雄激素影响。
