Buzzell G R
Department of Anatomy and Cell Biology, University Alberta, Edmonton, Canada.
Microsc Res Tech. 1996 Jun 1;34(2):133-8. doi: 10.1002/(SICI)1097-0029(19960601)34:2<133::AID-JEMT6>3.0.CO;2-T.
The Harderian gland of the Syrian hamster (Mesocricetus auratus) is unusual amongst rodents in the degree of dimorphism present. Other types of hamsters have Harderian glands which are apparently identical in male and female animals. Laboratory populations of Syrian hamsters are derived from very limited genetic stock, which makes one concerned lest they not be representative of wild populations; however, until wild stocks of M. auratus become available, we should assume that insights derived from studies of dimorphism in Syrian hamsters represent important considerations for the life of these animals. Two dimorphic features are the histology and the porphyrin content of the Harderian glands. About 95% of the lipid droplets in female glands are small (type 1), whereas only about 65% of those in males in type 1, with the other 35% being type 2 (large droplets). Five weeks of castration of males led to an increase in type 1 droplets to 90%. On the other hand, 2 weeks treatment of females with testosterone led to a reduction in type 1 droplets to about 82%. Short day photoperiods led to a large increase in type 2 droplets in both males and females (to 52% in males, 35% in females after 8 weeks). These results suggest that the lipid contained in type 2 droplets is important to hamsters of both sexes during the winter. Porphyrin concentrations are 100-1,000 times higher in females than males, and this is largely controlled by testosterone as orchidectomy leads to increased male levels and testosterone treatment leads to reduced female levels. However, a number of treatments which also lead to reduced testosterone levels do not lead to increased porphyrins and may, in fact, prevent the rise which would normally follow orchidectomy. One of these antiporphyrinogenic treatments is exposure to short day photoperiods. Thus, the sexual differences in porphyrin, levels in Syrian hamsters are maintained, despite seasonal fluctuations in hormone levels. This suggests that this dimorphism is important for the function of the gland.
叙利亚仓鼠（金仓鼠）的哈德氏腺在两性异形程度方面在啮齿动物中较为特殊。其他种类的仓鼠，其雄性和雌性动物的哈德氏腺显然是相同的。叙利亚仓鼠的实验种群源自非常有限的基因库，这让人担心它们可能无法代表野生种群；然而，在获得金仓鼠的野生种群之前，我们应该假定，从叙利亚仓鼠两性异形研究中获得的见解对这些动物的生活具有重要意义。两性异形的两个特征是哈德氏腺的组织学和卟啉含量。雌性腺体中约95%的脂滴较小（1型），而雄性中只有约65%的脂滴是1型，另外35%是2型（大脂滴）。雄性阉割5周后，1型脂滴增加到90%。另一方面，用睾酮对雌性进行2周治疗后，1型脂滴减少到约82%。短日照光周期导致雄性和雌性的2型脂滴大幅增加（8周后，雄性增加到52%，雌性增加到35%）。这些结果表明，2型脂滴中所含的脂质在冬季对两性仓鼠都很重要。雌性的卟啉浓度比雄性高100 - 1000倍，这在很大程度上受睾酮控制，因为睾丸切除会导致雄性卟啉水平升高，而睾酮治疗会导致雌性卟啉水平降低。然而，一些也会导致睾酮水平降低的处理并不会导致卟啉增加，实际上可能会阻止通常在睾丸切除后出现的卟啉升高。其中一种抗卟啉生成的处理方法是暴露于短日照光周期下。因此，尽管激素水平存在季节性波动，但叙利亚仓鼠卟啉水平的性别差异仍然存在。这表明这种两性异形对腺体功能很重要。
