title: Cellular localization of aquaporin-1 in the human and mouse trigeminal systems.
abstract: Previous studies reported that a subpopulation of mouse and rat trigeminal neurons express water channel aquaporin-1 (AQP1). In this study we make a comparative investigation of AQP1 localization in the human and mouse trigeminal systems. Immunohistochemistry and immunofluorescence results showed that AQP1 was localized to the cytoplasm and cell membrane of some medium and small-sized trigeminal neurons. Additionally, AQP1 was found in numerous peripheral trigeminal axons of humans and mice. In the central trigeminal root and brain stem, AQP1 was specifically expressed in astrocytes of humans, but was restricted to nerve fibers within the central trigeminal root and spinal trigeminal tract and nucleus in mice. Furthermore, AQP1 positive nerve fibers were present in the mucosal and submucosal layers of human and mouse oral tissues, but not in the muscular and subcutaneous layers. Fluorogold retrograde tracing demonstrated that AQP1 positive trigeminal neurons innervate the mucosa but not skin of cheek. These results reveal there are similarities and differences in the cellular localization of AQP1 between the human and mouse trigeminal systems. Selective expression of AQP1 in the trigeminal neurons innervating the oral mucosa indicates an involvement of AQP1 in oral sensory transduction.
authors.affiliation: Jiangsu Province Key Laboratory of Neurodegeneration, Department of Anatomy, Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Junying
authors.initials: J
authors.lastname: Gao
authors.forename: Meiyun
authors.initials: M
authors.lastname: Tan
authors.forename: Minxia
authors.initials: M
authors.lastname: Gu
authors.forename: Charles
authors.initials: C
authors.lastname: Marshall
authors.forename: Jiong
authors.initials: J
authors.lastname: Ding
authors.forename: Gang
authors.initials: G
authors.lastname: Hu
authors.forename: Ming
authors.initials: M
authors.lastname: Xiao
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D051398:Aquaporin 1 / Q000235:genetics*; D001253:Astrocytes / Q000378:metabolism* / Q000648:ultrastructure; D001344:Autopsy; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism; D003593:Cytoplasm / Q000235:genetics / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008813:Mice, Inbred ICR; D008875:Middle Aged; D009061:Mouth Mucosa / Q000502:physiology* / Q000648:ultrastructure; D009412:Nerve Fibers / Q000502:physiology / Q000648:ultrastructure; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure; D013045:Species Specificity; D009435:Synaptic Transmission / Q000502:physiology; D012668:Trigeminal Ganglion / Q000502:physiology* / Q000648:ultrastructure
chemical_list: D051398:Aquaporin 1