title: The chemical heterogeneity of cortical interneurons: nitric oxide synthase vs. calbindin and parvalbumin immunoreactivity in the rat.
abstract: Neurons that contain nitric oxide synthase (NOS) type I and the calcium binding proteins calbindin D28k or parvalbumin were simultaneously visualized by means of double immunohistofluorescence in the cerebral cortex of Wistar and Sprague-Dawley rats. All the three immunoreactive cell populations were primarily represented by nonpyramidal neurons. NOS-immunoreactive cells were less numerous than the calbindin- or parvalbumin-immunoreactive ones, and were intermingled with the neurons containing these calcium binding proteins. NOS-immunoreactive cells were separate from the parvalbumin-immunoreactive ones, whereas a minor proportion of them was found to be colocalized with calbindin. The cortical neurons in which NOS and calbindin coexisted were more numerous in the Sprague-Dawley than in the Wistar rats, and displayed an anteroposterior gradient of density, with the highest concentration in the medial prefrontal, frontal, and cingulate cortices. Double NOS-calbindin-immunoreactive neurons prevailed in the deep cortical layers and they were relatively numerous in the cingulate cortex. The present data indicate a selectivity in the expression of NOS vs. calbindin and parvalbumin in cortical cells, and further support the chemical heterogeneity of GABAergic interneurons in the cerebral cortex.
authors.affiliation: Institute of Anatomy and Histology, University of Verona, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Bertini
authors.forename: Z C
authors.initials: ZC
authors.lastname: Peng
authors.forename: M
authors.initials: M
authors.lastname: Bentivoglio
mesh_terms: D000818:Animals; D064092:Calbindin 1; D064026:Calbindins; D002540:Cerebral Cortex / Q000737:chemistry*; D005260:Female; D007150:Immunohistochemistry; D007395:Interneurons / Q000737:chemistry*; D008297:Male; D019001:Nitric Oxide Synthase / Q000276:immunology*; D010320:Parvalbumins / Q000276:immunology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D064030:S100 Calcium Binding Protein G / Q000276:immunology*
chemical_list: C576500:Calb1 protein, rat; D064092:Calbindin 1; D064026:Calbindins; D010320:Parvalbumins; D064030:S100 Calcium Binding Protein G; D019001:Nitric Oxide Synthase