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Forskolin enhanced off-response in the turtle olfactory system.

M Kashiwayanagi·H Kawahara·K Kurihara
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Abstract

Olfactory responses appear not only at the onset of odor stimulation, but also at the termination of the stimulation. It is widely considered that the cAMP-pathway is involved in the generation of odor responses. We examined how cAMP affects the generation of off-responses. To explore the role of the cAMP-pathway, odorants were applied to the turtle olfactory epithelium after forskolin at high concentrations which saturated the olfactory response to forskolin. Various odorants induced off-responses after 50 microM forskolin, indicating that off-responses are not induced via the cAMP-dependent pathway. However, the magnitude of the off-response after forskolin varied from 100 to 1400% of those of off-responses in its absence, indicating that forskolin greatly enhanced the off-responses to some odorants. The off-response after 0.1 mM citralva was also enhanced by 3 mM 8-(4-chlorophenylthio)-adenosine 3',5'-cyclic monophosphate (cpt-cAMP). These results suggested that cAMP modulates off-responses in the turtle olfactory system.

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1-Methyl-3-isobutylxanthineAnimalsColforsinCyclic AMPIon Channel GatingNeurons, AfferentOdorantsOlfactory MucosaSmellTurtlesJournal Article

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BibTeXRIS

M Kashiwayanagi, H Kawahara, K Kurihara. 1994. Forskolin enhanced off-response in the turtle olfactory system.. https://doi.org/10.1016/0928-4257(94)90011-6

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