THE OCCURRENCE OF A SUBUNIT PATTERN IN THE UNIT MEMBRANES OF CLUB ENDINGS IN MAUTHNER CELL SYNAPSES IN GOLDFISH BRAINS

作者：J. David Robertson · 发表于：The Journal of Cell Biology · 年份：1963 · DOI：10.1083/jcb.19.1.201 · 被引用次数：427 · 研究领域：Neuroscience and Neuropharmacology Research、Caveolin-1 and cellular processes、Connexins and lens biology

Observations additional to those previously reported (34) on boutons terminaux and club endings on Mauthner cell lateral dendrites, primarily as seen in sections of permanganate-fixed material, are described. Certain new findings on OSO(4)-fixed endings are also included. The boutons terminaux are closely packed in the synaptic bed with approximately 100 to 150 A gaps between their contiguous unit membranes and a few interspersed glial extensions. Their synaptic membrane complexes (SMC) appear as pairs of unit membranes separated by approximately 100 to 150A clefts. They contain many vesicles and unoriented mitochondria, but no neurofilaments. The club endings after KMnO(4) fixation are, as after OSO(4) fixation (34), again seen surrounded by a layer of extracellular matrix material. These endings contain relatively few synaptic vesicles, a few unit membrane limited tubules approximately 300 A in diameter, and mitochondria oriented perpendicular to the SMC. Neurotubules and neurofilaments are not clearly seen. These components are also virtually absent in the Mauthner cytoplasm. No ribosomes are seen in the KMnO(4)-fixed material. The unit membranes of the SMC of club endings show up clearly in essentially the same junctional relations described after formalin-OSO(4) fixation (34). In addition, the synaptic discs in transverse section show a central beading repeating at a period of approximately A associated with scalloping of the cytoplasmic surfaces. In oblique views, dense...