SEXUALLY DIMORPHIC EXPRESSION OF ANDROGEN RECEPTOR IMMUNOREACTIVITY BY SOMATOSTATIN NEURONS IN RAT HYPOTHALAMIC PERIVENTRICULAR NUCLEUS AND BED NUCLEUS OF THE STRIA TERMINALIS
SEXUALLY DIMORPHIC EXPRESSION OF ANDROGEN RECEPTOR IMMUNOREACTIVITY BY SOMATOSTATIN NEURONS IN RAT HYPOTHALAMIC PERIVENTRICULAR NUCLEUS AND BED NUCLEUS OF THE STRIA TERMINALIS
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DOI：
10.1111/j.1365-2826.1995.tb00791.x
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发表时间：
1995-07-01
影响因子：
3.2
通讯作者：
HERBISON, AE
中科院分区：
文献类型：
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作者：
HERBISON, AE
性腺类固醇激素对调节生长激素分泌的下丘脑神经元发挥重要的调节作用，并被认为在产生其分泌的性二态模式中发挥作用。最近的证据表明，雌激素对这些神经群体之一，脑室周围生长抑素（SOM）神经元的作用，可能是间接的，因为它们不具有核雌激素受体在任何性别，虽然雄激素受体（AR）已报告在这些细胞在雄性大鼠。本研究采用双标记免疫细胞化学方法，研究是否存在性别差异AR的SOM神经元位于室周核和床核的终纹（BNST）的表达。在下丘脑，SOM免疫反应阳性神经元被发现集中在室周核，而BNST的前部和后部分裂包含分散的SOM细胞群。在所有这些区域均检测到AR免疫反应性细胞。虽然AR细胞核染色的强度在男性和女性的区域，如外侧隔是相等的，AR染色的强度在许多个别细胞的室周核和后BNST的女性相比，男性减少。双标记实验显示，雄性大鼠室周SOM神经元中约40%表达AR免疫反应性，而雌性大鼠室周SOM神经元表达AR免疫反应性的细胞较少（约为7%），差异有显著性（P < 0.01）。在BNST中，双标记细胞仅在其后分裂的主包裹、束间和横核内检测到。雄鼠这些核团中约60%的SOM细胞表达AR，而雌鼠表达AR的细胞则明显少于雄鼠（P < 0.01）（约25%）。这些结果表明，实质性的性别差异存在AR的SOM神经元在室周核和BNST的表达。室周SOM细胞AR表达的这种差异可能有助于其性二态性的性质，因此，生长激素分泌的性别差异。
Gonadal steroids exert important regulatory actions on the hypothalamic neurones regulating growth hormone secretion and are believed to play a role in generating its sexually dimorphic pattern of secretion. Recent evidence indicates that estrogen actions on one of these neural populations, the periventricular somatostatin (SOM) neurones, are likely to be indirect as they do not possess nuclear estrogen receptors in either sex although androgen receptors (ARs) have been reported within these cells in male rats. The present study has used double-labelling immunocytochemistry procedures to examine whether sex differences exist in AR expression by SOM neurones located in the periventricular nucleus and bed nucleus of the stria terminalis (BNST). Within the hypothalamus, SOM-immunoreactive neurones were found concentrated in the periventricular nucleus while both anterior and posterior divisions of the BNST contained scattered populations of SOM cells. Cells immunoreactive for the AR were detected in all of these areas. Although the intensity of AR cell nuclei staining was equivalent in males and females in regions such as the lateral septum, the intensity of AR staining in many individual cells of the periventricular nucleus and posterior BNST of the female was reduced when compared with the male. Double-labelling experiments revealed that approximately 40% of periventricular SOM neurones expressed AR immunoreactivity in the male compared with significantly ; (P < 0.01) fewer cells in the female (similar to 7%). In the BNST, double-labelled cells were only detected within the principle encapsulated, interfascicular and transverse nuclei of its posterior division. Approximately 60% of SOM cells in these nuclei expressed AR immunoreactivity in the male while significantly (P < 0.01) fewer did so in the female (similar to 25%). These results indicate that substantial sex differences exist in AR expression by SOM neurones in both the periventricular nucleus and BNST. Such differences in AR expression by periventricular SOM cells may contribute to their sexually dimorphic nature and, consequently, sex differences in growth hormone secretion.