Nociceptin Signaling Involves a Calcium-Based Depolarization in Tetrahymena thermophila
Joint Authors
Kuruvilla, Heather
Lampert, Thomas
Nugent, Cheryl
Weston, John
Braun, Nathanael
Source
International Journal of Peptides
Issue
Vol. 2013, Issue 2013 (31 Dec. 2013), pp.1-7, 7 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2013-04-29
Country of Publication
Egypt
No. of Pages
7
Main Subjects
Abstract EN
Tetrahymena thermophila are free-living, ciliated eukaryotes.
Their behavioral response to stimuli is well characterized and easily observable, since cells swim toward chemoattractants and avoid chemorepellents.
Chemoattractant responses involve increased swim speed or a decreased change in swim direction, while chemorepellent signaling involves ciliary reversal, which causes the organism to jerk back and forth, swim in small circles, or spin in an attempt to get away from the repellent.
Many food sources, such as proteins, are chemoattractants for these organisms, while a variety of compounds are repellents.
Repellents in nature are thought to come from the secretions of predators or from ruptured organisms, which may serve as “danger” signals.
Interestingly, several peptides involved in vertebrate pain signaling are chemorepellents in Tetrahymena, including substances P, ACTH, PACAP, VIP, and nociceptin.
Here, we characterize the response of Tetrahymena thermophila to three different isoforms of nociceptin.
We find that G-protein inhibitors and tyrosine kinase inhibitors do not affect nociceptin avoidance.
However, the calcium chelator, EGTA, and the SERCA calcium ATPase inhibitor, thapsigargin, both inhibit nociceptin avoidance, implicating calcium in avoidance.
This result is confirmed by electrophysiology studies which show that 50 μM nociceptin-NH2 causes a sustained depolarization of approximately 40 mV, which is eliminated by the addition of extracellular EGTA.
American Psychological Association (APA)
Lampert, Thomas& Nugent, Cheryl& Weston, John& Braun, Nathanael& Kuruvilla, Heather. 2013. Nociceptin Signaling Involves a Calcium-Based Depolarization in Tetrahymena thermophila. International Journal of Peptides،Vol. 2013, no. 2013, pp.1-7.
https://search.emarefa.net/detail/BIM-481894
Modern Language Association (MLA)
Lampert, Thomas…[et al.]. Nociceptin Signaling Involves a Calcium-Based Depolarization in Tetrahymena thermophila. International Journal of Peptides No. 2013 (2013), pp.1-7.
https://search.emarefa.net/detail/BIM-481894
American Medical Association (AMA)
Lampert, Thomas& Nugent, Cheryl& Weston, John& Braun, Nathanael& Kuruvilla, Heather. Nociceptin Signaling Involves a Calcium-Based Depolarization in Tetrahymena thermophila. International Journal of Peptides. 2013. Vol. 2013, no. 2013, pp.1-7.
https://search.emarefa.net/detail/BIM-481894
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-481894