Rance N E, Young W S, McMullen N T
Department of Pathology, University of Arizona College of Medicine, Tucson 85724.
J Comp Neurol. 1994 Jan 22;339(4):573-86. doi: 10.1002/cne.903390408.
The distribution of neurons expressing luteinizing hormone-releasing hormone (LHRH) gene transcripts was mapped in the human hypothalamus and basal forebrain by in situ hybridization and computer-assisted microscopy. Hypothalamic blocks were dissected from five adult males and one adult female and snap frozen in isopentane. The blocks were serially sectioned either in the coronal or in the sagittal plane at a thickness of 20 microns. Approximately every twentieth section was incubated with a 35S-labeled cDNA probe complementary to LHRH mRNA. Specificity was confirmed by hybridization of adjacent sections with a probe targeted to the gonadotropin-associated protein (GAP) region of LHRH messenger ribonucleic acids (mRNA). Maps of neurons containing LHRH mRNA were manually digitized with the aid of an image-combining computer microscope system. We report a much wider distribution and greater numbers of LHRH neurons than have been previously described in the human brain. Three morphological subtypes were observed based on cell size and labeling density: 1) small, heavily labeled, oval or fusiform neurons, located primarily in the medial basal hypothalamus, ventral preoptic area, and periventricular zone; 2) small, oval, sparsely labeled neurons located in the septum and dorsal preoptic region and scattered from the bed nucleus of the stria terminalis to the amygdala ("extended amygdala"); and 3) large round neurons (> 500 microns 2 sectional profile area), intermediate in labeling density, scattered within the magnocellular basal forebrain complex, extended amygdala, ventral pallidum, and putamen. The pronounced differences in morphology, labeling density, and location of the three subtypes suggest that distinct functional subgroups of LHRH neurons exist in the human brain.
通过原位杂交和计算机辅助显微镜技术，绘制了人下丘脑和基底前脑表达促黄体生成激素释放激素（LHRH）基因转录本的神经元分布图。从五名成年男性和一名成年女性中取出下丘脑组织块，在异戊烷中速冻。将组织块在冠状面或矢状面以20微米的厚度连续切片。大约每隔二十张切片与一个与LHRH mRNA互补的35S标记cDNA探针孵育。通过用靶向LHRH信使核糖核酸（mRNA）促性腺激素相关蛋白（GAP）区域的探针与相邻切片杂交来确认特异性。借助图像组合计算机显微镜系统，手动数字化含有LHRH mRNA的神经元图谱。我们报告了LHRH神经元的分布比先前在人脑中描述的要广泛得多，数量也更多。根据细胞大小和标记密度观察到三种形态学亚型：1）小的、标记强烈的椭圆形或梭形神经元，主要位于内侧基底下丘脑、腹侧视前区和室周区；2）小的、椭圆形、标记稀疏的神经元，位于隔区和背侧视前区，从终纹床核到杏仁核（“扩展杏仁核”）散在分布；3）大的圆形神经元（截面轮廓面积>500平方微米），标记密度中等，散在于大细胞基底前脑复合体、扩展杏仁核、腹侧苍白球和壳核内。这三种亚型在形态、标记密度和位置上的明显差异表明，人脑中存在不同的LHRH神经元功能亚组。
