ADVANCEMENT OF SEXUAL-MATURATION IN MALE-RATS BY PITUITARY TRANSPLANTS
ADVANCEMENT OF SEXUAL-MATURATION IN MALE-RATS BY PITUITARY TRANSPLANTS
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DOI：
10.1095/biolreprod21.5.1263
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发表时间：
1979-01-01
影响因子：
3.6
通讯作者：
VANDERSCHOOT, P
中科院分区：
文献类型：
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作者：
DEJONG, RAP;VANDERSCHOOT, P
雄性大鼠出生时就有融合的巴拉诺包皮皱纹。这种皮褶的分裂依赖于雄激素，通常发生在生命的第40-45天。在这项研究中，我们重新研究了皮褶裂隙和雄激素之间的关系，特别注意了将这种裂隙作为一种简单和非创伤性的性成熟指标的可能性。然后进行了实验，以检验垂体移植(2只/只大鼠，在出生第21天植入)对性成熟的影响。与假手术大鼠相比，接受垂体移植的大鼠巴拉诺-包皮皱纹发生的时间提前了一周。卵裂的提前与青春期睾丸睾酮产量的增加有关。为了了解垂体移植分泌的催乳素是否可能与促进性成熟有关，我们进行了实验，研究了移植后初期垂体激素的释放；也研究了仅存在于21-23天龄的垂体移植对性成熟的影响，以及从移植前寄主的垂体移植耗尽腺体激素的影响。在后两组大鼠中，皮褶卵裂发生的年龄明显早于假手术组，但进展明显低于从第21天开始连续进行新鲜垂体移植的大鼠。这一结果与催乳素可能促进雄性大鼠性成熟的作用是一致的。然而，也不能排除其他脑下垂体激素的作用。如果移植后早期分泌的其他激素导致性早熟，这些激素对睾丸成熟的影响与对雌性大鼠卵巢成熟的影响有很大的不同：在后者，外源性激素一般在几天内促进性成熟。
Male rats are born with a fused balano-preputial skinfold. The cleavage of this skinfold is dependent on androgens and normally occurs about Day 40–45 of life. In the present study the relationship between skinfold cleavage and androgen was reexamined with particular attention to the possible use of this cleavage as an easy and nontraumatic index of sexual maturation.Experiments were then performed to examine the effect of pituitary transplants (2/rat, implantation on Day 21 of life) on sexual maturation. Balano-preputial skinfold cleavage occurred one week earlier in rats bearing pituitary grafts compared with sham operated rats. The advanced cleavage was associated with the advancement of the increase in testicular testosterone production at puberty.To find out whether prolactin, secreted by pituitary transplants, would possibly be responsible for advancement of sexual maturation, experiments were performed to study the release of pituitary hormones during the initial period after transplantation; also studied was the effect on sexual maturation of pituitary transplants that were present only between the ages of 21–23 days and of the presence from Day 21 onward of pituitary transplants that had been in hosts prior to transplantation to deplete the glands of hormones. In both of these latter groups of rats, the skinfold cleavage occurred at a significantly earlier age than in sham operated animals, but the advancement was significantly less than when freshly obtained pituitary transplants had been present continuously from Day 21 onwards.The results are consistent with a possible effect of prolactin to advance sexual maturation in male rats. However, the role of other pituitary hormones cannot be excluded. If the other hormones, secreted during the initial period after transplantation, establish premature sexual maturation, the time course of changes caused by these hormones on testicular maturation is greatly different from their effect on ovarian maturation in female rats: in the latter, exogenous hormones precipitate sexual maturation generally within a few days.