TISSUE DISTRIBUTION AND CELLULAR-LOCALIZATION OF THE LEVOCABASTINE-SENSITIVE NEUROTENSIN RECEPTOR MESSENGER-RNA IN ADULT-RAT BRAIN

The aim of this study was to determine the regional and cellular distr ibution of the neurotensin type 2 receptor (NT-2R) mRNA in the rat bra in. Using a radioactive in situ hybridization approach, the distributi on of NT-2R transcripts was quantified from autoradiograms, and the ce llular localization was examined in liquid emulsions. In rat brain, NT -2R mRNAs, are more widespread than the neurotensin type 1 receptor mR NA. NT-2R transcripts are diffusely distributed throughout the brain, with higher quantities found in the pia mater, the ventricles, the sub fornical organ, the subiculum, the substantia nigra, the ventral tegme ntal area, the superior colliculus, the periaqueductal gray matter, th e Purkinje cells and certain hypothalamic and brainstem nuclei. At the cellular level, silver grains appear to be concentrated on glia, neur ons and ependymal cells, such as cell bodies of the glia-rich corpus c allosum, Purkinje neurons in the cerebellum and ependymal cells lining the ventricles. In contrast, the thalamus and the amygdala contain lo w amounts of NT-2R mRNA. We discuss the anatomical location of NT-2R m RNA in relation to possible roles for this new receptor subtype. (C) 1 998 Elsevier Science B.V. All rights reserved.