Carballada R, Esponda P
Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
J Reprod Fertil. 1992 Aug;95(3):639-48. doi: 10.1530/jrf.0.0950639.
The relationship between the quantity of seminal vesicle secretion in the ejaculate, the percentage of spermatozoa reaching the uterus and fertility was studied in rats. Different portions of seminal vesicles were removed from male rats; 15 min after coitus (day 0), the numbers of spermatozoa in the uterus and vagina were counted and the vaginal plug characteristics were noted. Fertility was evaluated by the number of fetuses on day 14. A gradual decrease in the percentage of spermatozoa in the uterus was positively related to the reduction in seminal vesicle secretion, estimated by plug weight. This decline was not caused by a delay in sperm transport to the uterine lumen and the results suggested that the spermatozoa that fail to enter the uterus in the first minutes after coitus never enter. The vaginal plug weight, which is related to the seminal vesicle weight, and the position of the plug, which must be firmly lodged into the cervical opening, seem to be the most important conditions for promoting the rapid passage of spermatozoa into the uterus. When the seminal vesicles were partially removed, the plug was not tightly lodged and formed a 'cup' filled with spermatozoa. The number of fetuses did not show a close correlation with the quantity of seminal vesicle secretion. Studies of males in which the seminal vesicles had been removed indicated that a normal number of fetuses can be obtained despite low numbers of spermatozoa reaching the uterus. Ablation of the coagulating glands showed that, when there is no vaginal plug, no spermatozoa reach the uterus and fertility is suppressed. Nevertheless, the complete removal of coagulating glands is difficult; when small portions of these glands remain, the vaginal plug is formed and then fertility is achieved.
在大鼠中研究了射精时精囊分泌物的量、到达子宫的精子百分比与生育能力之间的关系。从雄性大鼠身上切除不同部分的精囊；交配后15分钟（第0天），对子宫和阴道中的精子数量进行计数，并记录阴道栓的特征。通过第14天的胎儿数量评估生育能力。子宫中精子百分比的逐渐下降与根据栓重量估计的精囊分泌物减少呈正相关。这种下降不是由精子向子宫腔运输的延迟引起的，结果表明在交配后最初几分钟未能进入子宫的精子永远不会进入。与精囊重量相关的阴道栓重量以及必须牢固地嵌入宫颈口的栓的位置，似乎是促进精子快速进入子宫的最重要条件。当部分切除精囊时，栓没有紧密嵌入，形成了一个充满精子的“杯状物”。胎儿数量与精囊分泌物的量没有密切相关性。对切除精囊的雄性大鼠的研究表明，尽管到达子宫的精子数量较少，但仍可获得正常数量的胎儿。对凝固腺的切除表明，当没有阴道栓时，没有精子到达子宫，生育能力受到抑制。然而，完全切除凝固腺很困难；当这些腺体的一小部分保留时，会形成阴道栓，然后实现生育能力。
