title: Immunocytochemical localization of carbonic anhydrase in the pseudobranch tissue of the rainbow trout Oncorhynchus mykiss.
abstract: Pseudobranch function has long interested scientists, but its role has yet to be elucidated. Several studies have suggested that pseudobranchs serve respiratory, osmoregulatory, and sensory functions. This work investigated the immunolocalization of pseudobranch carbonic anhydrase (CA) in the teleost fish species rainbow trout (Oncorhynchus mykiss) to clarify its physiological function. CA was purified from rainbow trout gills O. mykiss and specific antibodies were raised. Immunoblotting between tissue homogenates of pseudobranch and gill CA antibodies showed specific immunostaining with only one band corresponding to CA in the pseudobranch homogenate. Results of immunohistochemical technique revealed that CA was distributed within pseudobranch cells and more precisely in the apical parts (anti-vascular) of cells. The basal (vascular) parts of cells, tubular system, blood capillaries, and pillar cells were not immunostained. Immunocytochemistry confirmed these results and showed that some CA enzyme was cytoplasmic and the remainder was linked to membranous structures. The results also showed that the lacunar tissue layers did not display immunoperoxidase activity. Our results indicated that pseudobranch CA may have a function related to the extracellular medium wherein CA intervenes with the mechanism of stimulation of afferent nerve fibers.
authors: Department of Biology, Faculty of Education, University of Tikrit, 34001 Tikrit, Salah Al Deen, Iraq; School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia; Marine Ecosystem Research Centre, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia; Laboratoire de Diagnostic Génétique, Faculté de Médcine et CHRU, 67085 Strasbourg, France; Department of Biology, McMaster University, Hamilton, ON L8S 4K1, Canada.
authors: S M
authors: SM
authors: Rahim
authors: A G
authors: AG
authors: Mazlan
authors: K D
authors: KD
authors: Simon
authors: J P
authors: JP
authors: Delaunoy
authors: P
authors: P
authors: Laurent
mesh_terms: D000818:Animals; D002196:Capillaries / Q000378:metabolism; D002256:Carbonic Anhydrases / Q000378:metabolism*; D002846:Chromatography, Affinity; D003593:Cytoplasm / Q000378:metabolism; D005880:Gills / Q000201:enzymology; D007150:Immunohistochemistry; D017686:Oncorhynchus mykiss; D011817:Rabbits
chemical_list: D002256:Carbonic Anhydrases