title: Topographical distribution of corticotropin-releasing factor type 2 receptor-like immunoreactivity in the rat dorsal raphe nucleus: co-localization with tryptophan hydroxylase.
abstract: Corticotropin-releasing factor (CRF) and CRF-related neuropeptides are involved in the regulation of stress-related physiology and behavior. Members of the CRF family of neuropeptides bind to two known receptors, the CRF type 1 (CRF₁) receptor, and the CRF type 2 (CRF₂) receptor. Although the distribution of CRF₂ receptor mRNA expression has been extensively studied, the distribution of CRF₂ receptor protein has not been characterized. An area of the brain known to contain high levels of CRF₂ receptor mRNA expression and CRF₂ receptor binding is the dorsal raphe nucleus (DR). In the present study we investigated in detail the distribution of CRF₂ receptor immunoreactivity throughout the rostrocaudal extent of the DR. CRF₂ receptor-immunoreactive perikarya were observed throughout the DR, with the highest number and density in the mid-rostrocaudal DR. Dual immunofluorescence revealed that CRF₂ receptor immunoreactivity was frequently co-localized with tryptophan hydroxylase, a marker of serotonergic neurons. This study provides evidence that CRF₂ receptor protein is expressed in the DR, and that CRF₂ receptors are expressed in topographically organized subpopulations of cells in the DR, including serotonergic neurons. Furthermore, these data are consistent with the hypothesis that CRF₂ receptors play an important role in the regulation of stress-related physiology and behavior through actions on serotonergic and non-serotonergic neurons within the DR.
authors: Department of Integrative Physiology and Center for Neuroscience, University of Colorado Boulder, Boulder, CO 80309, USA. jodi.lukkes@colorado.edu
authors: J L
authors: JL
authors: Lukkes
authors: D R
authors: DR
authors: Staub
authors: A
authors: A
authors: Dietrich
authors: W
authors: W
authors: Truitt
authors: A
authors: A
authors: Neufeld-Cohen
authors: A
authors: A
authors: Chen
authors: P L
authors: PL
authors: Johnson
authors: A
authors: A
authors: Shekhar
authors: C A
authors: CA
authors: Lowry
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002461:Cell Line, Transformed; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D008297:Male; D011903:Raphe Nuclei / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018019:Receptors, Corticotropin-Releasing Hormone / Q000378:metabolism*; D014162:Transfection / Q000379:methods; D014365:Tryptophan Hydroxylase / Q000378:metabolism*
chemical_list: C101531:CRF receptor type 2; D018019:Receptors, Corticotropin-Releasing Hormone; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D014365:Tryptophan Hydroxylase