title: Localization of nicotinamide adenine dinucleotide phosphate-diaphorase activity in electrosensory and electromotor systems of a gymnotiform teleost, Apteronotus leptorhynchus.
abstract: The distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) activity was determined in electrosensory and electromotor systems of the weakly electric gymnotiform teleost Apteronotus leptorhynchus as an indicator of putative nitric oxide synthase-containing cells. NADPH-d activity was detected in electroreceptors and in afferent nerves of both ampullary and type I and type II tuberous organs. All cell bodies within the anterior lateral line nerve ganglion were positive for NADPH-d activity, as were the primary afferent axons and termination fields in the medullary electrosensory lateral line lobe. In the corpus cerebelli and valvula cerebelli, NADPH-d label was present in Purkinje cell somata, mossy fiber synaptic glomeruli, granule cells, and parallel fibers. In the midbrain, NADPH-d activity was apparent in layer VIIIB of the torus semicircularis dorsalis and in electrosensory laminae of the optic tectum. NADPH-d was particularly associated with diencephalic electrosensory and electromotor nuclei, including the prepacemaker nucleus, the nucleus subelectrosensorius, and the central posterior nucleus of the thalamus. Intense NADPH-d activity was present in pacemaker and relay cells of the medullary pacemaker nucleus but was absent from a novel class of smaller cells in this structure. Relay cell axons and spinal electromotor neurons and their axons within the electric organ were positive for NADPH-d activity. These results indicate that putative nitric oxide synthase-containing neurons in Apteronotus are localized preferentially to electrosensory and electromotor structures, suggesting a role for nitric oxide in determining the activity of cells involved in detecting or generating weakly electric fields.
authors.affiliation: Department of Medical Physiology, University of Calgary, Alberta, Canada.
authors.forename: R W
authors.initials: RW
authors.lastname: Turner
authors.forename: L L
authors.initials: LL
authors.lastname: Moroz
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D002531:Cerebellum / Q000378:metabolism; D004555:Electric Fish / Q000378:metabolism* / Q000502:physiology; D017950:Ganglia, Sensory / Q000201:enzymology* / Q000378:metabolism; D009046:Motor Neurons / Q000201:enzymology* / Q000378:metabolism; D009252:NADPH Dehydrogenase / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology; D011689:Purkinje Cells / Q000378:metabolism; D013116:Spinal Cord / Q000378:metabolism
chemical_list: D009569:Nitric Oxide; D009252:NADPH Dehydrogenase