Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons
Forskolin-induced Ca2+ signals were examined in isolated rat olfactory receptor neurons (ORNs) using a Ca2+ indicator, fura-2. In the soma of the ORNs, forskolin caused an increase in the intracellular Ca2+ concentration ([Ca2+]i) that was enhanced by a phosphodiesterase (PDE) 1 inhibitor, 8-methoxy...
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| Format: | Article |
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Elsevier
2005-01-01
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| Series: | Journal of Pharmacological Sciences |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1347861319322339 |
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| author | Ken-ichi Otsuguro Shree Hari Gautam Shigeo Ito Yoshiaki Habara Toshiyuki Saito |
| author_facet | Ken-ichi Otsuguro Shree Hari Gautam Shigeo Ito Yoshiaki Habara Toshiyuki Saito |
| author_sort | Ken-ichi Otsuguro |
| collection | DOAJ |
| description | Forskolin-induced Ca2+ signals were examined in isolated rat olfactory receptor neurons (ORNs) using a Ca2+ indicator, fura-2. In the soma of the ORNs, forskolin caused an increase in the intracellular Ca2+ concentration ([Ca2+]i) that was enhanced by a phosphodiesterase (PDE) 1 inhibitor, 8-methoxymethyl-3-isobutyl-1-methyl-xanthine, but not a PDE4 inhibitor, rolipram. Forskolin-induced Ca2+ signals were abolished with the removal of extracellular Ca2+ and un-affected by treatment with thapsigargin or caffeine plus ryanodine. Niflumic acid, a Ca2+-activated Cl- channel inhibitor, or nifedipine, an L-type Ca2+ channel inhibitor, slowed the initial rate of the increase in [Ca2+]i in response to forskolin. Nifedipine did not affect the increase in [Ca2+]i that was slowed by niflumic acid. In Ca2+ measurements with a confocal microscope and a calcium indicator, Fluo-4, the onset of the response to forskolin in the knob region occurred simultaneously or earlier, but not later, than that in the soma. It is suggested that the forskolin-induced Ca2+ signals are due to Ca2+ influx, but not the release of Ca2+ from Ca2+ stores, and that the initial rapid increase in [Ca2+]i is associated with the activation of the voltage-dependent Ca2+ channels in rat ORNs. Keywords:: olfactory receptor neuron, forskolin, Ca2+ signal, phosphodiesterase, Ca2+ channel |
| first_indexed | 2024-12-11T16:38:35Z |
| format | Article |
| id | doaj.art-f418a07c6d2c459f9e1d1af58f3e834e |
| institution | Directory Open Access Journal |
| issn | 1347-8613 |
| language | English |
| last_indexed | 2024-12-11T16:38:35Z |
| publishDate | 2005-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Pharmacological Sciences |
| spelling | doaj.art-f418a07c6d2c459f9e1d1af58f3e834e2022-12-22T00:58:23ZengElsevierJournal of Pharmacological Sciences1347-86132005-01-01974510518Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor NeuronsKen-ichi Otsuguro0Shree Hari Gautam1Shigeo Ito2Yoshiaki Habara3Toshiyuki Saito4Laboratory of Pharmacology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan; Corresponding author. FAX: +81-11-706-5220 E-mail: otsuguro@vetmed.hokudai.ac.jpLaboratory of Physiology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, JapanLaboratory of Pharmacology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, JapanLaboratory of Physiology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, JapanAnimal Neurophysiology Laboratory, National Institute of Agrobiological Sciences, Tsukuba 305-0901, JapanForskolin-induced Ca2+ signals were examined in isolated rat olfactory receptor neurons (ORNs) using a Ca2+ indicator, fura-2. In the soma of the ORNs, forskolin caused an increase in the intracellular Ca2+ concentration ([Ca2+]i) that was enhanced by a phosphodiesterase (PDE) 1 inhibitor, 8-methoxymethyl-3-isobutyl-1-methyl-xanthine, but not a PDE4 inhibitor, rolipram. Forskolin-induced Ca2+ signals were abolished with the removal of extracellular Ca2+ and un-affected by treatment with thapsigargin or caffeine plus ryanodine. Niflumic acid, a Ca2+-activated Cl- channel inhibitor, or nifedipine, an L-type Ca2+ channel inhibitor, slowed the initial rate of the increase in [Ca2+]i in response to forskolin. Nifedipine did not affect the increase in [Ca2+]i that was slowed by niflumic acid. In Ca2+ measurements with a confocal microscope and a calcium indicator, Fluo-4, the onset of the response to forskolin in the knob region occurred simultaneously or earlier, but not later, than that in the soma. It is suggested that the forskolin-induced Ca2+ signals are due to Ca2+ influx, but not the release of Ca2+ from Ca2+ stores, and that the initial rapid increase in [Ca2+]i is associated with the activation of the voltage-dependent Ca2+ channels in rat ORNs. Keywords:: olfactory receptor neuron, forskolin, Ca2+ signal, phosphodiesterase, Ca2+ channelhttp://www.sciencedirect.com/science/article/pii/S1347861319322339 |
| spellingShingle | Ken-ichi Otsuguro Shree Hari Gautam Shigeo Ito Yoshiaki Habara Toshiyuki Saito Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons Journal of Pharmacological Sciences |
| title | Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons |
| title_full | Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons |
| title_fullStr | Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons |
| title_full_unstemmed | Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons |
| title_short | Characterization of Forskolin-Induced Ca2+ Signals in Rat Olfactory Receptor Neurons |
| title_sort | characterization of forskolin induced ca2 signals in rat olfactory receptor neurons |
| url | http://www.sciencedirect.com/science/article/pii/S1347861319322339 |
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