Next Article in Journal
Comparative Study of Two Oxidizing Agents, Chloramine T and Iodo-Gen®, for the Radiolabeling of β-CIT with Iodine-131: Relevance for Parkinson’s Disease
Previous Article in Journal / Special Issue
Modulators of Transient Receptor Potential (TRP) Channels as Therapeutic Options in Lung Disease
Article Menu
Issue 1 (March) cover image

Export Article

Open AccessArticle
Pharmaceuticals 2019, 12(1), 24; https://doi.org/10.3390/ph12010024

Camphor, Applied Epidermally to the Back, Causes Snout- and Chest-Grooming in Rats: A Response Mediated by Cutaneous TRP Channels

1
Graduate Program in Neuroscience and Cognition, Federal University of ABC, São Bernardo do Campo 09606-070, SP, Brazil
2
Thermoregulation and Systemic Inflammation Laboratory (FeverLab), Trauma Research, St. Joseph’s Hospital and Medical Center, Phoenix, AZ 85013, USA
3
Center for Natural and Human Sciences, Federal University of ABC, São Bernardo do Campo 09606-070, SP, Brazil
*
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Received: 1 December 2018 / Revised: 21 January 2019 / Accepted: 31 January 2019 / Published: 2 February 2019
Full-Text   |   PDF [679 KB, uploaded 2 February 2019]   |  

Abstract

Thermoregulatory grooming, a behavioral defense against heat, is known to be driven by skin-temperature signals. Because at least some thermal cutaneous signals that drive heat defenses are likely to be generated by transient receptor potential (TRP) channels, we hypothesized that warmth-sensitive TRPs drive thermoregulatory grooming. Adult male Wistar rats were used. We showed that camphor, a nonselective agonist of several TRP channels, including vanilloid (V) 3, when applied epidermally to the back (500 mg/kg), caused a pronounced self-grooming response, including paw-licking and snout- and chest-“washing”. By the percentage of time spent grooming, the response was similar to the thermoregulatory grooming observed during exposure to ambient warmth (32 °C). Ruthenium red (a non-selective antagonist of TRP channels, including TRPV3), when administered intravenously at a dose of 0.1 mg/kg, attenuated the self-grooming behavior induced by either ambient warmth or epidermal camphor. Furthermore, the intravenous administration of AMG8432 (40 mg/kg), a relatively selective TRPV3 antagonist, also attenuated the self-grooming response to epidermal camphor. We conclude that camphor causes the self-grooming behavior by acting on TRP channels in the skin. We propose that cutaneous warmth signals mediated by TRP channels, possibly including TRPV3, drive thermoregulatory self-grooming in rats. View Full-Text
Keywords: AMG8432; anxiety; behavioral thermoregulation; body temperature; camphor; heat defenses; heat exposure; ruthenium red; thermoregulatory behaviors; TRPV3 AMG8432; anxiety; behavioral thermoregulation; body temperature; camphor; heat defenses; heat exposure; ruthenium red; thermoregulatory behaviors; TRPV3
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Ishikawa, D.T.; Vizin, R.C.L.; Souza, C.O.; Carrettiero, D.C.; Romanovsky, A.A.; Almeida, M.C. Camphor, Applied Epidermally to the Back, Causes Snout- and Chest-Grooming in Rats: A Response Mediated by Cutaneous TRP Channels. Pharmaceuticals 2019, 12, 24.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Pharmaceuticals EISSN 1424-8247 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top