Jennes L, Stumpf W E, Sheedy M E
J Comp Neurol. 1985 Feb 22;232(4):534-47. doi: 10.1002/cne.902320410.
By means of preembedding immunohistochemistry, two types of gonadotropin-releasing hormone (GnRH) positive neurons in the rat could be identified and characterized in the preoptic region and in the diagonal band: (1) a "smooth" GnRH neuron with relatively even cytoplasmic contours, and (2) a "spiny" GnRH neuron with thorn-like protrusions of the perikaryon and cell processes. Both cell types contain the same organelles in similar number and distribution, but they differ in the number of synaptic contacts. In general, GnRH cell bodies have a large round or ovoid nucleus, well-developed rough endoplasmic reticulum arranged in multilayered stacks or as individual cisternae, and several Golgi complexes. Lysosomes are not numerous under the conditions studied. Specializations include kinocilia, nematosomes, and lamellar whorls. Throughout the cytoplasm, scattered dense core vesicles with a diameter of 100 nm and clear vesicles with a diameter of 30-40 nm can be seen with a preferential localization close to the cell membrane. The cell processes of smooth GnRH cells close to the perikaryal appear as extensions of the perikaryal cytoplasm with all organelles except the nucleus. The two neurites originate from the perikaryon as tapering cones over a distance of 200-300 micron, until they reach a diameter of 0.5-3 micron. Cell processes of spiny GnRH cells show bifurcations, protrusions, or invaginations and contain clear and dense core vesicles in their spines. In areas distant from the perikaryon, immunoreactive fibers with a large number of dense core and clear vesicles can occasionally be seen to terminate synaptically or asynaptically on other neurons. The GnRH neurons show postsynaptic specializations at the level of the perikaryon and at cell processes, when apposed by a presynaptic terminal. Such synaptic contacts are seen less frequently on smooth cells than on spiny cells. Large areas of the GnRH cell may be covered by a thin glial lamella, which separates the cell body from the surrounding neuropil. The results indicate the existence of two populations of GnRH cell bodies with different patterns of innervation, which suggest different integrative capacities.
通过包埋前免疫组织化学方法，可以在大鼠视前区和斜角带中识别并表征两种促性腺激素释放激素（GnRH）阳性神经元：（1）一种“光滑型”GnRH神经元，其细胞质轮廓相对均匀；（2）一种“棘型”GnRH神经元，其核周体和细胞突起有刺状突出。两种细胞类型含有数量和分布相似的相同细胞器，但它们的突触接触数量不同。一般来说，GnRH细胞体有一个大的圆形或椭圆形细胞核、排列成多层堆叠或单个池状的发达粗面内质网以及几个高尔基体复合物。在所研究的条件下，溶酶体数量不多。特化结构包括动纤毛、线虫小体和板层小体。在整个细胞质中，可以看到直径为100nm的散在致密核心小泡和直径为30 - 40nm的清亮小泡，优先定位在靠近细胞膜处。靠近核周体的光滑型GnRH细胞的细胞突起表现为核周体细胞质的延伸，除细胞核外包含所有细胞器。两条神经突从核周体以逐渐变细的圆锥状起始，在200 - 300微米的距离内，直至达到直径0.5 - 3微米。棘型GnRH细胞的细胞突起显示出分支、突出或内陷，并且在其棘中含有清亮和致密核心小泡。在远离核周体的区域，偶尔可以看到带有大量致密核心和清亮小泡的免疫反应性纤维在其他神经元上突触性或非突触性终止。当与突触前终末并置时，GnRH神经元在核周体水平和细胞突起处显示出突触后特化结构。这种突触接触在光滑型细胞上比在棘型细胞上少见。GnRH细胞的大片区域可能被一层薄的神经胶质板覆盖，该神经胶质板将细胞体与周围神经毡分隔开。结果表明存在两种具有不同神经支配模式的GnRH细胞体群体，这表明它们具有不同的整合能力。
