title: Distribution and chemical coding pattern of somatostatin immunoreactivity in the dorsal striatum of the guinea pig.
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.
authors.affiliation: Department of Comparative Anatomy, Faculty of Biology, University of Warmia and Mazury in Olsztyn, Poland. bachaw@uwm.edu.pl
authors.forename: Barbara
authors.initials: B
authors.lastname: Wasilewska
authors.forename: Anna
authors.initials: A
authors.lastname: Robak
authors.forename: Maciej
authors.initials: M
authors.lastname: Równiak
authors.forename: Krystyna
authors.initials: K
authors.lastname: Bogus-Nowakowska
authors.forename: Janusz
authors.initials: J
authors.lastname: Najdzion
authors.forename: Witold
authors.initials: W
authors.lastname: Zakowski
authors.forename: Mariusz
authors.initials: M
authors.lastname: Majewski
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000737:chemistry* / Q000378:metabolism; D005260:Female; D006168:Guinea Pigs; D009412:Nerve Fibers / Q000737:chemistry / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D009478:Neuropeptide Y / Q000032:analysis / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000032:analysis / Q000378:metabolism; D013004:Somatostatin / Q000032:analysis* / Q000378:metabolism
chemical_list: D009478:Neuropeptide Y; D013004:Somatostatin; D019001:Nitric Oxide Synthase