Herbison A E, Horvath T L, Naftolin F, Leranth C
Laboratory of Neuroendocrinology, Babraham Institute, Cambridge, UK.
Neuroendocrinology. 1995 Jan;61(1):1-10. doi: 10.1159/000126810.
The precise sites and mechanisms by which gonadal steroids influence the activity of neuroendocrine cells controlling pituitary hormone secretion are poorly understood. The present study has determined the distribution of estrogen receptor (ER)-immunoreactive cells in the monkey hypothalamus and examined whether ERs are expressed by luteinising hormone-releasing hormone (LHRH)-and/or dopamine-containing neurones. The distribution of ER-immunoreactive cells was determined in ovariectomised (n = 2) and estrogen plus progesterone-treated (n = 2) cynomolgus macaques and in a single ovariectomised African green monkey. Large numbers of cells immunoreactive for the ER were detected in the preoptic area, bed nucleus of the stria terminalis, periventricular area and ventromedial and arcuate nuclei of all monkeys irrespective of the steroid status. Smaller numbers of ER-immunoreactive cells were found in the paraventricular, but not supraoptic nucleus. Double-labeling experiments in sections from all 5 monkeys revealed that none of the 432 LHRH neurons examined possessed detectable ER immunoreactivity. Neurones stained for tyrosine hydroxylase (TH) were identified in the A11, A12, and A14 cell groups and, although A11 and A12 neurones were intermingled amongst and found adjacent to ER-immunoreactive cells, none of the 1,652 TH-immunoreactive cells examined contained ER immunoreactivity. These results show that ER-immunoreactive cells in the monkey hypothalamus are distributed in a manner similar to that observed in other mammalian species although not all brain regions reported to contain progesterone receptors (PRs) in these species of monkey were found to express ERs. The double-labelling experiments provide further evidence that LHRH neurones do not possess ERs and indicate that, as in other species, estrogen influences on primate LHRH neurones are indirect and/or non-genomic in nature. Unlike the rat and sheep, no evidence was found for ER immunoreactivity in hypothalamic dopaminergic neurones of the monkey. The discrepancy in ER and reported PR receptor localisation within specific hypothalamic nuclei as well as in dopaminergic neurones raises the possibility that not all PR-containing cells may express ERs in the primate hypothalamus.
性腺类固醇影响控制垂体激素分泌的神经内分泌细胞活性的精确部位和机制目前还知之甚少。本研究确定了雌激素受体（ER）免疫反应性细胞在猴下丘脑的分布，并检测了促黄体生成素释放激素（LHRH）和/或含多巴胺神经元是否表达ER。在去卵巢（n = 2）和雌激素加孕酮处理（n = 2）的食蟹猕猴以及一只去卵巢的非洲绿猴中确定了ER免疫反应性细胞的分布。无论类固醇状态如何，在所有猴子的视前区、终纹床核、室周区以及腹内侧核和弓状核中都检测到大量对ER免疫反应的细胞。在室旁核中发现了较少数量的ER免疫反应性细胞，但视上核中没有。对所有5只猴子切片进行的双重标记实验显示，在所检查的432个LHRH神经元中，没有一个具有可检测到的ER免疫反应性。在A11、A12和A14细胞群中鉴定出了酪氨酸羟化酶（TH）染色的神经元，尽管A11和A12神经元与ER免疫反应性细胞混合并相邻，但在所检查的1652个TH免疫反应性细胞中，没有一个含有ER免疫反应性。这些结果表明，猴下丘脑的ER免疫反应性细胞的分布方式与在其他哺乳动物物种中观察到的相似，尽管在这些猴物种中，并非所有据报道含有孕激素受体（PR）的脑区都被发现表达ER。双重标记实验进一步证明LHRH神经元不具有ER，并表明与其他物种一样，雌激素对灵长类LHRH神经元的影响是间接的和/或非基因组性质的。与大鼠和绵羊不同，在猴的下丘脑多巴胺能神经元中未发现ER免疫反应性的证据。ER和报道的PR受体在特定下丘脑核以及多巴胺能神经元中的定位差异增加了在灵长类下丘脑并非所有含PR的细胞都可能表达ER的可能性。
