Balthazart J, Tlemçani O, Harada N
Laboratory of Biochemistry, University of Liege, Belgium.
J Chem Neuroanat. 1996 Sep;11(3):147-71. doi: 10.1016/0891-0618(96)00149-4.
The distribution of aromatase-immunoreactive cells was studied in the medial preoptic nucleus of male and female quail that were sexually mature and gonadally intact, or gonadectomized, or gonadectomized and treated with testosterone. The study first confirmed the existence of a significant difference in the number of aromatase-immunoreactive cells between males and females (males > females) and the marked effect of castration and testosterone treatment which, respectively, decrease and restore the number of these cells. An analysis of the distribution in space of this neurochemically defined cell population was also carried out. This study revealed that castration does not uniformly decrease the density of aromatase-immunoreactive cells, but local increases are observed in an area directly adjacent to the third ventricle. A number of new sex differences in the organization of the medial preoptic nucleus and its population of aromatase cells have, in addition, been identified. The density of aromatase-immunoreactive cells is not higher in males than in females throughout the nucleus, but a higher density of immunoreactive cells is present in the ventromedial part of the nucleus in females as compared to males. In addition, the cross-sectional area of the nucleus as defined by the population of aromatase-immunoreactive cells is larger in males than in females in its rostral part and its shape is more elongated in the dorso-ventral direction in females than in males. Some of these differences (e.g. higher density of ARC-ir cells in the ventromedial part of the female POM, shape of the nucleus) appear to be organizational in nature, because they are still present in birds exposed to the same endocrine conditions during adult life (e.g. gonadectomized and treated with a same dose of testosterone). This conclusion should now be tested by experiments manipulating the endocrine environment of quail embryos. The anatomical heterogeneity of the medial preoptic nucleus revealed by this study also suggests a functional heterogeneity and the specific roles of the medial and lateral parts of the nucleus should also be investigated.
研究了性成熟且性腺完整、或已去势、或已去势并用睾酮处理的雄性和雌性鹌鹑视前内侧核中芳香化酶免疫反应性细胞的分布。该研究首先证实了雄性和雌性之间芳香化酶免疫反应性细胞数量存在显著差异（雄性>雌性），以及去势和睾酮处理的显著影响，去势和睾酮处理分别减少和恢复了这些细胞的数量。还对这个神经化学定义的细胞群体的空间分布进行了分析。该研究表明，去势并不会均匀地降低芳香化酶免疫反应性细胞的密度，而是在紧邻第三脑室的区域观察到局部增加。此外，还发现了视前内侧核及其芳香化酶细胞群体组织中的一些新的性别差异。在整个核中，雄性芳香化酶免疫反应性细胞的密度并不高于雌性，但与雄性相比，雌性核的腹内侧部分存在更高密度的免疫反应性细胞。此外，由芳香化酶免疫反应性细胞群体定义的核的横截面积在雄性的 Rostral 部分大于雌性，并且雌性核在背腹方向上的形状比雄性更细长。其中一些差异（例如雌性视前内侧核腹内侧部分 ARC-ir 细胞密度更高、核的形状）似乎具有组织学性质，因为它们在成年期暴露于相同内分泌条件的鸟类中仍然存在（例如去势并用相同剂量的睾酮处理）。现在应该通过操纵鹌鹑胚胎内分泌环境的实验来验证这一结论。该研究揭示的视前内侧核的解剖学异质性也表明存在功能异质性，并且还应该研究该核内侧和外侧部分的特定作用。
