caa a22 4500 46794394X CHVBK 20180405193735.0 cr unu---uuuuu 170328e20050201xx s 000 0 eng 10.1007/s11055-005-0046-9 doi (NATIONALLICENCE)springer-10.1007/s11055-005-0046-9 (NATIONALLICENCE)springer-10.1007/s11055-005-0001-9 Distribution of calcium ions in the mixed synapses of Mauthner neurons in the goldfish in normal conditions, in exhaustion, and in conditions of adaptation to exhaustion [Elektronische Daten] [D. Moshkov, E. Bezgina, L. Pavlik, N. Mukhtasimova, T. Mavlyutov] The aim of this study was to investigate the structure of large myelinated club terminals of Mauthner neurons (MN) in the goldfish at different levels of functional activity and the distribution within these synapses of calcium ions as assessed using a modified pyroantimonate method. In intact preparations, calcium pyroantimonate precipitates were not seen in gap junctions (GJ) or desmosome-like contacts (DLC). Fibrillar bridges in DLC clefts were not contrasted. After natural stimulation, which induces long-term adaptation in MN, GJ showed electron-dense precipitates lining the whole cleft. Granules and clumps of precipitate were also seen in DLC clefts, with intense deposition on bridges. Increases in calcium ion concentrations to and above the levels detectable by the pyroantimonate method are known to block electrotonic transmission; filamentous actin is known to conduct the electrotonic signal as a cation current. The staining of DLC bridges with calcium pyroantimonate is therefore evidence for an association between calcium ions and actin molecules, as DLC bridges consist of actin, i.e., we have obtained evidence for the functioning of bridges as electrotonic transsynaptic shunts at the moment of fixation. These data lead to the conclusion that DLC in mixed synapses, apart from the known adhesive functions, also have a communication function. This appears in extreme conditions, allowing the synapse to maintain or change its conductivity according to ongoing need. Springer Science+Business Media, Inc., 2005 mauthner neuron nationallicence functional activity nationallicence mixed synapses nationallicence calcium ions nationallicence Moshkov D. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut Bezgina E. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut Pavlik L. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut Mukhtasimova N. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut Mavlyutov T. Scientific Center for Biophysics and Physiology, Pushchino State University, Pushchino aut Neuroscience and Behavioral Physiology Kluwer Academic Publishers-Consultants Bureau 35/2(2005-02-01), 117-122 0097-0549 35:2<117 2005 35 11055 https://doi.org/10.1007/s11055-005-0046-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11055-005-0046-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Moshkov D. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut NATIONALLICENCE 700 1- Bezgina E. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut NATIONALLICENCE 700 1- Pavlik L. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut NATIONALLICENCE 700 1- Mukhtasimova N. Neuron Ultrastructure Laboratory, Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino aut NATIONALLICENCE 700 1- Mavlyutov T. Scientific Center for Biophysics and Physiology, Pushchino State University, Pushchino aut NATIONALLICENCE 773 0- Neuroscience and Behavioral Physiology Kluwer Academic Publishers-Consultants Bureau 35/2(2005-02-01), 117-122 0097-0549 35:2<117 2005 35 11055 NATIONALLICENCE 856 40 https://doi.org/10.1007/s11055-005-0001-9 text/html Onlinezugriff via DOI Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE NATIONALLICENCE NL-springer