Neuron-glial contacts formed in the cerebellum during electrical stimulation in the presence of an NO-generating compound.
The molecular layer of the cerebellum of the frog Rana temporaria was studied by light and electron microscopy after electrical stimulation in the presence of an NO-generating compound. In these conditions, there was severe swelling of granule cell axon terminals (boutons) and astrocyte processes (AP), with loss of cytoplasmic elements. However, along with damaged structures, there were also undamaged structures: boutons with synaptic vesicles and AP with glycogen granules. It is suggested that these persisting viable AP may form 1) glial "wrappings" around damaged synapses or boutons and 2) neuron-glial contacts, which form when synaptic vesicles cross damaged bouton membranes to AP containing glycogen granules. It is also suggested that the presence of glycogen in AP in conditions of oxygen and glucose deficiency may provide a source of high-energy substrates such as glucose and ATP, thus providing conditions for neuron survival in pathological states (ischemia/hypoxia).
Samosudova
N V
NV
Laboratory No. 12, Institute of Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia.
Reutov
V P
VP
Larionova
N P
NP
Chailakhyan
L M
LM
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure*; D002531:Cerebellum / Q000187:drug effects / Q000648:ultrastructure*; D004558:Electric Stimulation; D018698:Glutamic Acid / Q000378:metabolism / Q000494:pharmacology; D006003:Glycogen / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D017729:Presynaptic Terminals / Q000187:drug effects / Q000648:ultrastructure*; D011689:Purkinje Cells / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure*; D011896:Rana temporaria; D013572:Synaptic Vesicles / Q000648:ultrastructure
D020030:Nitric Oxide Donors; D009569:Nitric Oxide; D018698:Glutamic Acid; D006003:Glycogen