Vol 49, No 4 (2011)
Original paper
Published online: 2012-01-16
Distribution and chemical coding pattern of somatostatin immunoreactivity in the dorsal striatum of the guinea pig
DOI: 10.5603/FHC.2011.0093
Folia Histochem Cytobiol 2011;49(4):690-699.
Abstract
The present study provides a detailed description of somatostatin (SOM) distribution and the colocalization
pattern of SOM, neuropeptide Y (NPY) and nitric oxide synthase (NOS) in the dorsal striatum
(caudate-putamen complex) of the guinea pig. Within the dorsal striatum, SOM is found in a population of
medium-sized aspiny interneurons. We found that 97% of all SOM-IR neurons expressed NPY simultaneously,
while 98% of all NPY-ergic perikarya was simultaneously SOM-IR. On the other hand, while 98% of all SOM-IR
cells were simultaneously NOS-IR, only 91% of all NOS-containing neurons exhibited SOM-immunoreactivity.
Irrespective of their chemical coding, both types of SOM-IR neurons were scattered throughout the dorsal
striatum, sometimes in the form of small, loosely arranged clusters of 2–4 cells. While SOM-IR and NPY-IR
nerve fibers were present in all of the studied regions, they were more numerous in the ventro-medial part of the
studied structure, with the exception of its caudal portion, where SOM-IR and NPY-IR fibers additionally formed
a dense network in the part corresponding to the caudate nucleus. A low expression of staining for NOS-IR fibers
was seen throughout the entire dorsal striatum. In some fibers, SOM and NPY were co-expressed. Fibers expressing
both SOM and NOS were not found. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 690–699)
Keywords: somatostatinnitric oxide synthaseneuropeptide Ydorsal striatumguinea pig
![](https://journals.viamedica.pl/plugins/generic/popups/images/icons/close.png)