Neuropeptide-containing neurons in the endopiriform region of the rat: morphology and colocalization with calcium-binding proteins and nitric oxide synthase.
The endopiriform nucleus, further divided into dorsal and ventral parts, and the neighbouring pre-endopiriform (pEn) nucleus form a region of highly heterogeneous structure involved in numerous physiological and pathological processes. Nonpyramidal neurons of this region containing three neuropeptides-somatostatin (SOM), neuropeptide Y (NPY), and vasoactive intestinal peptide (VIP)-were examined in this study. Their colocalization with three calcium-binding proteins-parvalbumin (PV), calbindin D28k (CB), calretinin (CR), and with nitric oxide synthase (NOS), was investigated by qualitative and quantitative methods. The results are summarized as follows: (1) all studied substances are distributed in neurons of the entire region, (2) SOM-ir neurons constitute the most numerous neuropeptide-containing population, whereas NOS-ir neurons make up the largest population of all studied, (3) colocalizations are found in the endopiriform region (Enr) (SOM with CB, PV and NOS; VIP with CR; NPY with NOS and NOS with CR), (4) heterogeneity of the endopiriform region appears in the differences of cells' shape distributions of single-labeled (SOM-, CR-PV-ir) and double-labeled (SOM/CB-, SOM/PV-, NPY/NOS- and NOS/CR-ir) neurons, as well as in differentiated percentage values of SOM/NOS, NPY/NOS and VIP/CR double-labeled neurons in three studied parts; additionally, differences in distribution of immunoreactive neuropil elements between parts of the region are observed. Numerous regional differences concerning neuronal morphology and immunocytochemical characteristics justify further division of the endopiriform region into distinguished parts. Some immunocytochemical features of the neurons in studied region may contribute to the role in epileptogenesis.
Kowiański
Przemysław
P
Department of Anatomy and Neurobiology, Medical University of Gdańsk, 1 Debinki Street, 80-211, Gdańsk, Poland. kowiansk@amg.gda.pl
Moryś
Joanna M
JM
Wójcik
Sławomir
S
Dziewiatkowski
Jerzy
J
Luczyńska
Anna
A
Spodnik
Edyta
E
Timmermans
Jean-Pierre
JP
Moryś
Janusz
J
D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002452:Cell Count; D048429:Cell Size; D002540:Cerebral Cortex / Q000166:cytology*; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D009474:Neurons / Q000145:classification / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D051381:Rats
D002135:Calcium-Binding Proteins; D009479:Neuropeptides; D019001:Nitric Oxide Synthase