Fine structure and synaptology of the nitrergic neurons in medial septum of the rat brain.
The nitrergic neuron population and certain aspects of their connectivity (peptidergic inputs, co-localization with GABA, synaptic target distribution) were studied in the medial septum of the rat brain. The histochemical localization of NADPH diaphorase and immunohistochemical identification of nNOS at light and electron microscopic level was applied. Double-labeling experiments with galanin and leucine enkephalin, moreover the postembedding GABA immunogold staining was also carried out. NADPH diaphorase- and nNOS-immunopositive neurons could be identified inside the borders of medial septum. Out of their peptidergic inputs galanin- and leucine enkephaline-immunopositive varicose fibers were found in close apposition with nNOS-immunopositive neurons. Based on fine structural characteristics (large indented nucleus, thin cytoplasmic rim, lack of axosomatic synapses) the nitrergic neurons are suggested to be identical with the septal cholinergic nerve cells. Their boutons established asymmetrical synapses mainly on dendritic shafts and spines, some of which were also nNOS-immunopositive. A lower amount of nNOS-immunopositive boutons of presumably extrinsic origin were found to be GABAergic.
Department of Anatomy and Histology, University of Veterinary Sciences , H-1078 Budapest, István u. 2 . Hungary.
Katalin
K
Halasy
Department of Anatomy and Histology, University of Veterinary Sciences , H-1078 Budapest, István u. 2 . Hungary.
Balázs
B
Szőke
Department of Anatomy and Histology, University of Veterinary Sciences , H-1078 Budapest, István u. 2 . Hungary.
Gergely
G
Janzsó
D000818:Animals; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008854:Microscopy, Electron / Q000379:methods*; D009252:NADPH Dehydrogenase / Q000378:metabolism; D026602:Nitrergic Neurons / Q000378:metabolism / Q000648:ultrastructure*; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D017208:Rats, Wistar; D020665:Septum of Brain / Q000378:metabolism / Q000648:ultrastructure*; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D005680:gamma-Aminobutyric Acid; D052248:Nitric Oxide Synthase Type I; D009252:NADPH Dehydrogenase
GABA-synaptology; NADPH; nNOS; neuropeptides