Abstract
The fine structure of the electric organ of the fish Torpedo marmorata has been examined after osmium tetroxide or potassium permanganate fixation, acetone dehydration, and Araldite embedment. This organ consists of stacks of electroplaques which possess a dorsal noninnervated and a ventral richly innervated surface. Both surfaces are covered with a thin basement membrane. A tubular membranous network whose lumen is continuous with the extracellular space occupies the dorsal third of the electroplaque. Nerve endings, separated from the ventral surface of the electroplaque by a thin basement membrane, contain synaptic vesicles (diameter 300 to 1200 A), mitochondria, and electron-opaque granules (diameter 300 A). Projections from the nerve endings occupy the lumina of the finger-like invaginations of the ventral surface. The cytoplasm of the electroplaques contains the usual organelles. A "cellular cuff" surrounds most of the nerve fibers in the intercellular space, and is separated from the nerve fibre and its Schwann cell by a space containing connective tissue fibrils. The connective tissue fibrils and fibroblasts in the intercellular space are primarily associated with the dorsal surface of the electroplaque.
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Selected References
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- ALTAMIRANO M., COATES C. W., GRUNDFEST H. Mechanisms of direct and neural excitability in electroplaques of electric eel. J Gen Physiol. 1955 Jan 20;38(3):319–360. doi: 10.1085/jgp.38.3.319. [DOI] [PMC free article] [PubMed] [Google Scholar]
- BIRKS R., HUXLEY H. E., KATZ B. The fine structure of the neuromuscular junction of the frog. J Physiol. 1960 Jan;150:134–144. doi: 10.1113/jphysiol.1960.sp006378. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GRAY E. G. Electron microscopy of presynaptic organelles of the spinal cord. J Anat. 1963 Jan;97:101–106. [PMC free article] [PubMed] [Google Scholar]
- LUFT J. H. Permanganate; a new fixative for electron microscopy. J Biophys Biochem Cytol. 1956 Nov 25;2(6):799–802. doi: 10.1083/jcb.2.6.799. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LUFT J. H. The fine structure of the electric organ of the electric eel and torpedo ray; preliminary communication. J Biophys Biochem Cytol. 1956 Jul 25;2(4 Suppl):229–232. doi: 10.1083/jcb.2.4.229. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MILLONIG G. A modified procedure for lead staining of thin sections. J Biophys Biochem Cytol. 1961 Dec;11:736–739. doi: 10.1083/jcb.11.3.736. [DOI] [PMC free article] [PubMed] [Google Scholar]
- NATHANIEL E. J., PEASE D. C. COLLAGEN AND BASEMENT MEMBRANE FORMATION BY SCHWANN CELLS DURING NERVE REGENERATION. J Ultrastruct Res. 1963 Dec;52:550–560. doi: 10.1016/s0022-5320(63)80084-2. [DOI] [PubMed] [Google Scholar]
- PALADE G. E. A study of fixation for electron microscopy. J Exp Med. 1952 Mar;95(3):285–298. doi: 10.1084/jem.95.3.285. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PALAY S. L. Synapses in the central nervous system. J Biophys Biochem Cytol. 1956 Jul 25;2(4 Suppl):193–202. doi: 10.1083/jcb.2.4.193. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PALAY S. L. The morphology of synapses in the central nervous system. Exp Cell Res. 1958;14(Suppl 5):275–293. [PubMed] [Google Scholar]
- REVEL J. P., NAPOLITANO L., FAWCETT D. W. Identification of glycogen in electron micrographs of thin tissue sections. J Biophys Biochem Cytol. 1960 Dec;8:575–589. doi: 10.1083/jcb.8.3.575. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ROBERTSON J. D., BODENHEIMER T. S., STAGE D. E. THE ULTRASTRUCTURE OF MAUTHNER CELL SYNAPSES AND NODES IN GOLDFISH BRAINS. J Cell Biol. 1963 Oct;19:159–199. doi: 10.1083/jcb.19.1.159. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ROBERTSON J. D. The ultrastructure of a reptilian myoneural junction. J Biophys Biochem Cytol. 1956 Jul 25;2(4):381–394. doi: 10.1083/jcb.2.4.381. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SABATINI D. D., BENSCH K., BARRNETT R. J. Cytochemistry and electron microscopy. The preservation of cellular ultrastructure and enzymatic activity by aldehyde fixation. J Cell Biol. 1963 Apr;17:19–58. doi: 10.1083/jcb.17.1.19. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SHANTHAVEERAPPA T. R., BOURNE G. H. A perineural epithelium. J Cell Biol. 1962 Aug;14:343–346. doi: 10.1083/jcb.14.2.343. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SHANTHAVEERAPPA T. R., BOURNE G. H. The 'perineural epithelium', a metabolically active, continuous, protoplasmic cell barrier surrounding peripheral nerve fasciculi. J Anat. 1962 Oct;96:527–537. [PMC free article] [PubMed] [Google Scholar]
- TERRY R. D., HARKIN J. C. Regenerating peripheral nerve sheaths following wallerian degeneration. Exp Cell Res. 1957 Aug;13(1):193–197. doi: 10.1016/0014-4827(57)90069-1. [DOI] [PubMed] [Google Scholar]
- TERRY R. D., HARKIN J. C. Wallerian degeneration and regeneration of peripheral nerves. Prog Neurobiol. 1959;4:303–320. [PubMed] [Google Scholar]
- WACHTEL A., MATHEWSON R., GRUNDFEST H. Electron microscopic and histochemical comparison of the two types of electroplaques of Narcine brasiliensis. J Biophys Biochem Cytol. 1961 Dec;11:663–675. doi: 10.1083/jcb.11.3.663. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WATSON M. L. The nuclear envelope; its structure and relation to cytoplasmic membranes. J Biophys Biochem Cytol. 1955 May 25;1(3):257–270. doi: 10.1083/jcb.1.3.257. [DOI] [PMC free article] [PubMed] [Google Scholar]
- YAMAMOTO T. Some observations on the fine structure of the sympathetic ganglion of bullfrog. J Cell Biol. 1963 Jan;16:159–170. doi: 10.1083/jcb.16.1.159. [DOI] [PMC free article] [PubMed] [Google Scholar]