2194.2 Expression and Localization of p-Glu Serpinin
in the Central Nervous System
Studies on the expression of serpinin and pGlu-serpinin revealed that there are specific
areas in the central nervous system (CNS) where serpinin is present in significant
amounts. Using an antibody specific for pGlu-serpinin, immunohistochemistry stud-
ies in mouse brain revealed that one of the areas enriched in this peptide is in the pars
reticulate of the substantia nigra, (Fig. 5A, a). This region is the major source of
GABAergic innervation to various brain areas (mainly thalamus) and also the region
which receives axons from medium spiny cells from the striatum, as well as
GABAergic projections from globus pallidium and glutaminergic projections from
subthalamic nucleus (Kanazawa and Toyokura 1975 ; Tepper and Lee 2007 ). Indeed,
it has been reported that many GABAergic neurons express CgA (Schafer et al. 2010 )
and pGlu-serpinin are likely in axons of these neurons. Another region of the brain
showing expression of pGlu-serpinin in the parafascicular nucleus (Fig. 5A, b), which
is an intralaminar nucleus of the thalamus, typically considered as part of the ascend-
ing activating system and is homologous to the human center median. Parafascicular
nucleus is an essential source of thalamostriatal projections (Tsumori et al. 2003 ;
Vercelli et al. 2003 ). pGlu-serpinin is also present in the nuclei of pontis (Fig. 5B),
which are the concentrations of the gray matter of the pons and are involved basically
GL
ONL
A C
B
abb accFig. 5 Immunohistochemical staining for pGlu-serpinin in mouse brain sections. (A) Arrows
show immuno-staining in the area of the Substantia Nigra (a), and the Nucleus Centrum-
parafacicularis Thalami (b). (B) Arrow points to the Nuclei Pontis (c). (C) The olfactory bulb
showing immuno-staining in the Glomerular layer (GL) and the olfactory nerve layer (ONL)
Serpinin Peptides: Tissue Distribution and Functions