title: Using high resolution imaging to determine trafficking of corticotropin-releasing factor receptors in noradrenergic neurons of the rat locus coeruleus.
abstract: Trafficking of G protein-coupled receptors (GPCRs) is a critical determinant of cellular sensitivity of neurons. To understand how endogenous or exogenous ligands impact cell surface expression of GPCRs, it is essential to employ approaches that achieve superior anatomical resolution at the synaptic level. In situations in which light and fluorescence microscopy techniques may provide only limited resolution, electron microscopy provides enhanced subcellular precision. Dual labeling immunohistochemistry employing visually distinct immunoperoxidase and immunogold markers has been an effective approach for elucidating complex receptor profiles at the synapse and to definitively establish the localization of individual receptors and neuromodulators to common cellular profiles. The immuno-electron microscopy approach offers the potential for determining membrane versus intracellular protein localization, as well as the association with various identifiable cellular organelles. Corticotropin-releasing factor (CRF) is an important regulator of endocrine, autonomic, immunological, behavioral and cognitive limbs of the stress response. Dysfunction of this neuropeptide system has been associated with several psychiatric disorders. This review summarizes findings from neuroanatomical studies, with superior spatial resolution, that indicate that the distribution of CRF receptors is a highly dynamic process that, in addition to being sexually dimorphic, involves complex regulation of receptor trafficking within extrasynaptic sites that have significant consequences for adaptations to stress, particularly within the locus coeruleus (LC), the major brain norepinephrine-containing nucleus.
authors: Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, United States. Electronic address: Beverly.Reyes@drexelmed.edu.
authors: B A S
authors: BA
authors: Reyes
authors: Psychology Department and Neuroscience Program, Temple University, Philadelphia, PA 19122, United States.
authors: D A
authors: DA
authors: Bangasser
authors: Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States.
authors: R J
authors: RJ
authors: Valentino
authors: Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102, United States.
authors: E J
authors: EJ
authors: Van Bockstaele
mesh_terms: D059331:Adrenergic Neurons / Q000502:physiology* / Q000648:ultrastructure; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D005260:Female; D007124:Immunoenzyme Techniques; D008125:Locus Coeruleus / Q000502:physiology* / Q000648:ultrastructure; D008297:Male; D016253:Microscopy, Immunoelectron; D057054:Molecular Imaging; D021381:Protein Transport; D051381:Rats; D018019:Receptors, Corticotropin-Releasing Hormone / Q000378:metabolism*; D012737:Sex Factors; D013312:Stress, Physiological; D013569:Synapses / Q000502:physiology* / Q000648:ultrastructure
chemical_list: D018019:Receptors, Corticotropin-Releasing Hormone; D003346:Corticotropin-Releasing Hormone
keywords: Corticotropin-releasing factor; Corticotropin-releasing factor receptor; Locus coeruleus; Norepinephrine