遭受营养不良、阉割及性腺激素治疗的大鼠颅骨中两性异形的变化。

Variations in sexual dimorphism in the skulls of rats subjected to malnutrition, castration, and treatment with gonadal hormones.

作者信息

Dahinten S L, Pucciarelli H M

出版信息

Am J Phys Anthropol. 1986 Sep;71(1):63-7. doi: 10.1002/ajpa.1330710108.

Abstract

Two groups of weanling rats were subjected to malnutrition, one with periodic injections of testosterone (males) and the other with estradiol (females). Two other groups (castrated males or castrated females) received normal feedings. In control animals, the relative weights (mg/gm body weight) of testes, seminal vesicles, and ovaries were greater than in malnourished rats. However, relative weights of those organs in hormone-treated, malnourished animals were greater than in those subjected to malnutrition alone and still greater than in controls. Normal sexual cranial dimorphism (SCD) was decreased 16% by male castration, 23% by malnutrition, and 83% by estradiol treatment in malnourished females. On the other hand, normal SCD was increased 20% by female castration and more than 200% by testosterone treatment in malnourished males. All monosexual comparisons corroborated the bisexual range of distances found. Testicular but not ovarian secretions seemed to influence sexual cranial dimorphism. Malnutrition delayed SCD because of a deficiency of testosterone level in stressed males. It is suggested that estradiol in females may counteract sexual cranial development and that its inhibitory effect may be additive to the testosterone deficit evoked by malnutrition.

摘要

将两组断乳大鼠置于营养不良状态，一组定期注射睾酮（雄性），另一组定期注射雌二醇（雌性）。另外两组（去势雄性或去势雌性）给予正常饮食。在对照动物中，睾丸、精囊和卵巢的相对重量（毫克/克体重）高于营养不良的大鼠。然而，激素处理的营养不良动物中这些器官的相对重量高于仅接受营养不良处理的动物，且仍高于对照动物。正常的性颅二态性（SCD）在雄性去势后降低了16%，在营养不良时降低了23%，在营养不良的雌性中经雌二醇处理后降低了83%。另一方面，正常的SCD在雌性去势后增加了20%，在营养不良的雄性中经睾酮处理后增加了200%以上。所有单性别的比较都证实了所发现的两性距离范围。睾丸而非卵巢的分泌物似乎影响性颅二态性。营养不良会延迟SCD，这是由于应激雄性大鼠睾酮水平不足所致。研究表明，雌性中的雌二醇可能会抵消性颅发育，并且其抑制作用可能会叠加营养不良所引发的睾酮缺乏效应。