Barkley M, DeLeon D D, Weste R
Department of Animal Physiology, University of California, Davis 95616.
J Exp Zool. 1993 Apr 1;265(5):558-66. doi: 10.1002/jez.1402650512.
The role of male pheromones in estrous cyclicity was studied in mice selected for different reproductive traits. When females are exposed to males of their own strain, estrous cycles are highly regular in females selected for increased embryo survival (line E). In contrast, cycle regularity is reduced by exposure of line E females to males from a strain characterized by irregular estrous cycles (line CN-). To investigate the inhibition of estrous cyclicity and the role of androgen in this phenomenon, line E females were housed in the olfactory presence of E males and later rehoused with one of the following: intact or castrated males of line E (homogenotypic condition) or line CN-heterogenotypic condition) or castrated CN- males provided with testosterone replacement. A final exposure to homogenotypic (line E) males was provided. Estrous cyclicity was decreased when line E females were rehoused with intact or castrated CN- males. Metestrus was prolonged by intact CN- males, whereas diestrus was prolonged in the presence of castrated CN- males. Androgen treatment did not enable castrated CN- males to prolong metestrus. These results demonstrate that: 1) heterogenotypic pheromones inhibit estrous cyclicity in line E; and 2) the inhibitory influence of line CN- males on line E estrous cyclicity is mediated by factors in addition to or other than testosterone.
在具有不同生殖特征的小鼠中研究了雄性信息素在发情周期中的作用。当雌性小鼠暴露于同品系雄性时，在选择用于提高胚胎存活率的雌性小鼠（E系）中，发情周期高度规律。相比之下，将E系雌性小鼠暴露于来自具有不规律发情周期品系（CN-系）的雄性小鼠中，会降低周期规律性。为了研究发情周期的抑制作用以及雄激素在这一现象中的作用，将E系雌性小鼠饲养在有E系雄性小鼠气味的环境中，之后再与以下之一重新饲养：E系完整或阉割的雄性小鼠（同基因型条件）或CN-系雄性小鼠（异基因型条件），或给予睾酮替代的阉割CN-系雄性小鼠。最后让其再次暴露于同基因型（E系）雄性小鼠中。当E系雌性小鼠与完整或阉割的CN-系雄性小鼠重新饲养时，发情周期缩短。完整的CN-系雄性小鼠会延长动情后期，而在阉割的CN-系雄性小鼠存在的情况下会延长间情期。雄激素处理并不能使阉割的CN-系雄性小鼠延长动情后期。这些结果表明：1）异基因型信息素会抑制E系小鼠的发情周期；2）CN-系雄性小鼠对E系发情周期的抑制作用是由睾酮以外的因素介导的。
