Belenky M A, Chetverukhin V K, Polenov A L
Cell Tissue Res. 1979 Dec;204(2):333-42. doi: 10.1007/BF00234644.
The distribution of monoaminergic structures was studied in the proximal neurosecretory contact region and neurohypophysis of the lamprey by light and electron microscopic radioautography. Only weak radioautographic reactions were found in the proximal neurosecretory contact region 1 h after injection of 3H-dopamine. High-resolution radioautography revealed some labeled neurosecretory terminals mainly in contact with the basement membrane of the connective tissue layer separating the proximal neurosecretory contact region from the hypophysial pars distalis. The number of silver grains as well as the number of neurosecretory terminals marked by the presence of labeled dopamine was much higher in the neurohypophysis of the same species. In the latter, labeled neurosecretory terminals were found in contact with the connective tissue layer containing blood vessels of the general circulation. Some neurosecretory terminals make synaptoid contacts with tanycyte perikarya and their basal processes. According to their ultrastructure and the size of their granules, the labeled neurosecretory terminals are identical with the B type terminals described in both neurohemal regions (transmission electron microscopy). No labeled neurosecretory terminals were observed in the proximal neurosecretory contact region and the neurohypophysis of lampreys treated with the serotonin precursor, 3H-5-hydroxytryptophan.
通过光镜和电镜放射自显影技术，研究了七鳃鳗近端神经分泌接触区和神经垂体中单胺能结构的分布。注射3H-多巴胺1小时后，在近端神经分泌接触区仅发现微弱的放射自显影反应。高分辨率放射自显影显示，一些标记的神经分泌终末主要与将近端神经分泌接触区与垂体远侧部分隔开的结缔组织层的基底膜接触。在同一物种的神经垂体中，银粒数量以及由标记多巴胺显示的神经分泌终末数量要高得多。在后者中，发现标记的神经分泌终末与含有体循环血管的结缔组织层接触。一些神经分泌终末与室管膜周细胞及其基底突起形成类突触接触。根据其超微结构和颗粒大小，标记的神经分泌终末与在两个神经血器官区域中描述的B型终末相同（透射电子显微镜）。在用血清素前体3H-5-羟色氨酸处理的七鳃鳗的近端神经分泌接触区和神经垂体中未观察到标记的神经分泌终末。
