Localization Of Nitric-oxide Synthase In The Mouse Olfactory And Vomeronasal System - A Histochemical, Immunological And In-situ Hybridization Study
accessory olfactory bulb; brain; messenger-rna; nadph-diaphorase activity; napdh diaphorase; napdh-p450 oxidoreductase; Neurosciences & Neurology; olfactory bulb; protein; reductase
The distribution of nitric oxide synthase (NOS) in the mouse olfactory bulb and olfactory epithelium, including the vomeronasal organ, was studied using an anti-NOS antibody, NADPH diaphorase histochemistry and in situ hybridization with NOS specific antisense oligonucleotide probes. Interneurons containing NOS protein and mRNA, and exhibiting NADPH diaphorase activity were detected in the plexiform layer of the main olfactory bulb and the granule cell layer of main and accessory olfactory bulbs. Periglomerular cells and granule cells in the main olfactory bulb were also NOS positive with diaphorase and immunostaining for NOS. In contrast, no evidence for NOS expression was found either in the main olfactory epithelium or in the vomeronasal organ, in spite of the strong diaphorase staining of the surface of the main olfactory epithelium. Polymerase chain reaction amplification experiments for detection of NOS gene expression further indicated that NOS is expressed in the olfactory bulb but not in either the main olfactory epithelium or vomeronasal organ. Use of an antibody raised against another enzyme, NADPH-P450 oxidoreductase, showed that this protein was strongly expressed in the olfactory epithelium, Activity of this enzyme may account for the diaphorase histochemical staining of the epithelia. An involvement of neuronal nitric oxide synthase in signalling in olfactory receptor neurons is therefore doubtful, although NOS is clearly expressed in neurons in both main and accessory olfactory bulbs.
Kishimoto J; Keverne E B; Hardwick J; Emson P C
European Journal of Neuroscience
1993
1993-12
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1111/j.1460-9568.1993.tb00236.x" target="_blank" rel="noreferrer noopener">10.1111/j.1460-9568.1993.tb00236.x</a>
Aquatic adaptation and the evolution of smell and taste in whales.
Antarctic minke whale genome; Archaeoceti; Cetacea; Chemoreception; Olfactory bulb
INTRODUCTION: While olfaction is one of the most important senses in most terrestrial mammals, it is absent in modern toothed whales (Odontoceti, Cetacea). Furthermore, behavioral evidence suggests that gustation is very limited. In contrast, their aquatic sistergroup, baleen whales (Mysticeti) retain small but functional olfactory organs, and nothing is known about their gustation. It is difficult to investigate mysticete chemosensory abilities because experiments in a controlled setting are impossible. RESULTS: Here, we use the functional regionalization of the olfactory bulb (OB) to identify the loss of specific olfactory functions in mysticetes. We provide the whole-genome sequence of a mysticete and show that mysticetes lack the dorsal domain of the OB, an area known to induce innate avoidance behavior against odors of predators and spoiled foods. Genomic and fossil data suggest that mysticetes lost the dorsal domain of the OB before the Odontoceti-Mysticeti split. Furthermore, we found that all modern cetaceans are revealed to have lost the functional taste receptors. CONCLUSION: These results strongly indicate that profound changes in the chemosensory capabilities had occurred in the cetacean lineage during the period when ancestral whales migrated from land to water.
Kishida Takushi; Thewissen J G M; Hayakawa Takashi; Imai Hiroo; Agata Kiyokazu
Zoological letters
2015
1905-07
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1186/s40851-014-0002-z" target="_blank" rel="noreferrer noopener">10.1186/s40851-014-0002-z</a>