Somato-dendritic synapses in the nucleus reticularis thalami of the rat.
In the reticular nucleus of the rat thalamus, about 30% of the synapses are brought about by the perikarya of parvalbumin-immunopositive neurons, which establish somato-dendritic synapses with large dendrites of nerve cells of specific thalamic nuclei. Although the parvalbumin-immunopositive presynaptic structures bear resemblance to goblet-like or calyciform axonal endings, electron microscopic immunocytochemistry and in situ hybridization revealed that these structures are parts of the perikaryal cytoplasm studded with synaptic vesicles. In about 15% of the somato-dendritic synapses, axons are seen to be in synaptic contact with the parvalbumin-immunoreactive perikaryon. Double immunohistochemical staining revealed that the parvalbumin immunoreactive presynaptic perikarya and dendrites contained GABA. It is assumed that the peculiar somato-dendritic synaptic complexes subserve the goal of filtration of impulses arriving at the reticular nucleus from various thalamic nuclei, thus processing them for further sampling.
Csillik
B
B
Department of Anatomy, Albert Szent-Györgyi Medical and Pharmaceutical Center, University of Szeged, Hungary. csillik@anat-fm.szote.u-szeged.hu
Pálfi
A
A
Gulya
K
K
Mihály
A
A
Knyihár-Csillik
Elizabeth
E
D000818:Animals; D003712:Dendrites / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D016253:Microscopy, Immunoelectron; D010320:Parvalbumins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure*; D013787:Thalamic Nuclei / Q000378:metabolism / Q000648:ultrastructure*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D010320:Parvalbumins; D005680:gamma-Aminobutyric Acid