Transient increase of calcium in pre- and postsynaptic organelles of rat superior cervical ganglion after tetanizing stimulation.
The stimulation-dependent translocation and redistribution of intracellular calcium was studied in synapses of the rat superior cervical ganglion. For the cytochemical demonstration of calcium at the ultrastructural level the oxalate-pyroantimonate technique was used. Calcium-containing deposits were observed as electron-dense particles in synaptic vesicles and occasionally in presynaptic mitochondria. On the postsynaptic side, vesicles and vacuoles in dendrites contained increased amounts of reaction product. Following a short train of impulses (20 s, 20 c.p.s.), the ganglionic response to a single stimulus was increased. This potentiation effect which lasted about 1-5 min was accompanied by a change in the distribution of calcium at fine structural level. In ganglia fixed 1 and 5 min after the train, but not later, the number of calcium-containing synaptic vesicles and postsynaptic vacuoles increased significantly.
Institute of Biophysics, Biological Research Center, Szeged, Hungary.
A
A
Párducz
J
J
Toldi
F
F
Joó
L
L
Siklós
J R
JR
Wolff
D000818:Animals; D000965:Antimony; D002118:Calcium / Q000032:analysis / Q000502:physiology*; D004558:Electric Stimulation; D005404:Fixatives; D005727:Ganglia, Spinal / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D006651:Histocytochemistry; D008854:Microscopy, Electron; D010070:Oxalates; D019815:Oxalic Acid; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D013572:Synaptic Vesicles / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure
D005404:Fixatives; D010070:Oxalates; C009133:pyroantimonate; D019815:Oxalic Acid; D000965:Antimony; D002118:Calcium