Uno H, Hökfelt T
Cell Tissue Res. 1975;158(1):1-13. doi: 10.1007/BF00219948.
The external layer of the median eminence (ELME) and the arculate nucleus of male rats were studied with the Falck-Hillarp technique and electron microscopy of aldehyde-OsO4 or KMnO4 fixed after various types of hypothalamic deafferentation experiments with the Halász knife. Special reference was paid to the monoamine systems and the results can be summarized as follows. 1. The main monoaminergic input to the ELME comes from the arcuate nucleus-periventricular area via a dorsal approach. A horizontal transection through the arcuate nucleus decreases the percentage of monoamine boutons i.e. boutons with small granular vesicles, from 31.6% in the controls to 4.4% in the lesion group, whereas only a small effect is seen after anterior (or complete) deafferentations. 2. A major input to the ELME enters the basal hypothalamus at the anterior-lateral aspects (see Réthelyi and Halász, 1970). The fibers cut after anterior deafferentations in all probability mainly come from cell bodies localized in the anterior hypothalamus or even further rostrally but some may represent NA axons ascending from the lower brain stem. 3. The degeneration course of nerve endings in the ELME both after anterior deafferentations as well as after lesions in the arcuate nucleus is rapid (within 2-3 days) and morphologically characterized by an initial aggregation of large dense cored vesicles seemingly to electron dense bodies within the boutons and probably also to a closer spacing of the small electron lucent synaptic vesicles (see Raisman, 1972). This type of degeneration seems to take place both in monoamine and non-monoamine neurons. 4. Degenerating boutons are found in the arcuate nucleus after anterior and complete deafferentations. Thus, the anterior hypothalamus may exert an "indirect" control of the pituitary gland via synapses on arcuate neurons although quantitatively the "direct" influence through the projection to the ELME is of more importance. 5. After anterior deafferentations enlarged axons containing large amounts of large dense cored vesicles and other organelles are found caudally of the cut indicating the existence of rostral projections from the medial hypothalamus.
采用Falck-Hillarp技术以及醛-锇酸或高锰酸钾固定后的电子显微镜技术，对经Halász刀进行各种类型下丘脑去传入实验后的雄性大鼠正中隆起外层（ELME）和弓状核进行了研究。特别关注了单胺系统，结果总结如下。1. 对ELME的主要单胺能输入通过背侧途径来自弓状核-室周区域。通过弓状核的水平横切使单胺终扣（即含有小颗粒小泡的终扣）的百分比从对照组的31.6%降至损伤组的4.4%，而在前侧（或完全）去传入后仅观察到较小的影响。2. 对ELME的主要输入从前外侧进入下丘脑底部（见Réthelyi和Halász，1970）。在前侧去传入后切断的纤维很可能主要来自位于下丘脑前部甚至更靠前部位的细胞体，但有些可能代表从脑干下部上行的去甲肾上腺素能轴突。3. 在前侧去传入以及弓状核损伤后，ELME中神经末梢的变性过程迅速（在2 - 3天内），形态学特征为大的致密核心小泡最初聚集在终扣内形成电子致密体，并且小的电子透亮突触小泡间距可能也更近（见Raisman，1972）。这种变性似乎发生在单胺能和非单胺能神经元中。4. 在前侧和完全去传入后，在弓状核中发现了变性终扣。因此，下丘脑前部可能通过与弓状神经元的突触对垂体施加“间接”控制，尽管从数量上看，通过投射到ELME的“直接”影响更为重要。5. 在前侧去传入后，在切断部位尾侧发现含有大量大的致密核心小泡和其他细胞器的增粗轴突，表明下丘脑内侧存在向头侧的投射。
